@Hedda @ShadowFist - Thank you both for the detailed technical breakdown.
You’re correct on the Zigbee 4.0/Suzi technical points:
• No Suzi devices exist today
• No Silicon Labs SDK for Zigbee 4.0 yet
• ZBT-2 will receive Zigbee 4.0 features via firmware update (for 2.4GHz band)
• Early adopter challenges are real (Matter rollout proves this)
I understand the technical limitations. However, I respectfully disagree with the conclusion that NabuCasa “did the right thing by forging ahead” with the November 2025 release.
Here’s why:
THE TIMING ARGUMENT - Still Valid
Let me clarify my position on timing, because I think it’s being misunderstood.
I’m NOT suggesting NC should have “cancelled launch last minute” or “scrapped production mid-cycle.”
I’m suggesting the launch timeline itself was poorly planned:
ZBT-1: October 2022
ZBT-2: November 2025 (3 years later)
ZBT-2 with Zigbee 4.0/Suzi: Late 2026 or H1 2027 (4-4.5 years later)
Waiting until late 2026/early 2027 would have been a perfectly reasonable product cycle - actually closer to industry standards (Philips: 4+ years between major releases).
@Hedda, you mentioned “you are complaining about ZBT-2 not supporting devices that do not yet exist” - but that’s precisely my point. If NC had planned a late 2026/H1 2027 release instead of rushing to market in Nov 2025, those devices WOULD exist by launch time, and ZBT-2 could have been a complete, future-proof product like ZWA-2.
THE ECONOMIC ARGUMENT - User Perspective
From a user value standpoint:
Software bugs → Fixed via free updates ✓
Hardware limitations (no Suzi) → Requires purchasing new coordinator ($49)
Current path:
• ZBT-2 (Nov 2025): $49 - Zigbee 3.0 only
• ZBT-3 (2026/27?): $49 - Zigbee 4.0 + Suzi
• Total cost: $98
Better path:
• ZBT-2 with Zigbee 4.0/Suzi (late 2026): $69 - Complete solution
• Total cost: $69
The “wait for better tech” argument works BOTH ways. Yes, you can always wait for next-gen tech. But when that next-gen tech is announced literally ONE DAY before your product launch, the timing becomes commercially questionable.
THE MARKET REALITY - Who’s Actually Buying?
Let’s be honest about who will purchase ZBT-2 now vs later:
Will buy ZBT-2 today:
• Enthusiasts supporting the HA project (like me)
• Users who don’t follow Zigbee spec announcements
• People prioritizing design aesthetics
Will wait for ZBT-3:
• Existing ZBT-1 users who want meaningful tech upgrade
• Users who read this forum and know Zigbee 4.0/Suzi is coming
• Smart home builders planning 5+ year installations
By releasing ZBT-2 one day after Zigbee 4.0 announcement, NC essentially created a “wait for next version” scenario for a significant portion of their potential customer base.
That’s not optimal product strategy.
THE ACTUAL VALUE PROPOSITION - What Are We Really Buying?
Let’s analyze what ZBT-2 actually offers over ZBT-1:
4x baud rate improvement (115.2k → 460.8k bps)? Yes, this is a real technical upgrade for internal communication speed. I acknowledge this improvement.
However, for end-user experience, the difference between “instant” and “4x more instant” is marginal. Zigbee device response is primarily limited by mesh hop latency and device firmware, not coordinator serial speed.
Improved range? In Zigbee, mesh quality depends on router/repeater quantity and placement, not primarily on coordinator antenna specs.
Future-proof tech? Missing Zigbee 4.0 hardware (Suzi), so no.
Better HA integration? Actually worse than ZWA-2:
• LED control entity disappears after firmware update
• No status sensor (ZWA-2 has both)
• ~12+ users experiencing firmware installation failures
Better design? Yes - genuinely excellent industrial design.
So realistically, we’re buying:
- 4x serial communication speed (nice-to-have, minimal user impact)
- Premium design aesthetics (significant value)
- Support for the HA/NabuCasa project (primary value)
Those are valid reasons! But they’re not the comprehensive technical superiority reasons marketed in “The best gets better” blog post.
THE INTEGRATION REGRESSION - Critical Issue
Speaking of ZWA-2 comparison, here’s what concerns me most:
ZWA-2 (launched October 2025):
• LED control entity ✓
• Status sensor ✓
• Tilt detection with accelerometer (LED blinks if not upright) ✓
ZBT-2 (launched November 2025):
• LED control entity: Present initially, DISAPPEARS after firmware update ✗
• Status sensor: Missing ✗
• Tilt detection: Not mentioned in specs, not available in HA integration ✗
Question: Does ZBT-2 have accelerometer hardware that’s simply not exposed in HA integration? If the hardware exists but isn’t accessible - why not? If it doesn’t exist - why the regression compared to ZWA-2?
This is a genuine question because I can’t find this information in official specs or community discussions.
The broader issue: Why does the NEWER product (ZBT-2, Nov 2025) deliver LESS complete Home Assistant integration than the OLDER product (ZWA-2, Oct 2025)?
THE DAY-ONE QUALITY PROBLEM - This Cannot Be Dismissed
@ShadowFist, you mentioned early adopter teething issues if ZBT-2 had launched with Zigbee 4.0 in 2026.
But we’re experiencing teething issues RIGHT NOW with the current Nov 2025 release:
• ~12+ users with firmware installation failures (ZBT-2 Error - Zigbee firmware failed to install, check Home Assistant logs for more information)
• LED control entity regression (present initially, disappears post-update)
• Missing status sensor (ZWA-2 has this)
• Workarounds required: web flasher, manual procedures, device power cycles
Compare to ZWA-2 (launched Oct 2025):
• Zero firmware issues
• Complete entity integration
• True plug-and-play experience
• Genuinely “rock-solid” as marketed
So the “avoid early adopter issues by shipping stable tech” argument doesn’t hold - we’re dealing with day-one stability issues anyway.
The critical difference is: ZWA-2’s issues (if any) can be fixed via software updates. ZBT-2’s missing Zigbee 4.0 hardware cannot.
The 4x speed improvement is real, but it doesn’t compensate for missing LED control, missing status sensor, and firmware installation failures affecting day-one user experience.
THE UNANSWERED QUESTION - Critical for Users
As someone experiencing these integration issues, I need clarity from NabuCasa:
Are the missing entities (LED control, status sensor, potential tilt detection) a software bug that will be patched?
Or is this a hardware/firmware limitation of current ZBT-2 units?
Should I:
a) Keep the unit and wait for software fixes?
b) Return it as defective and wait for a corrected hardware batch?
This directly impacts support decisions for users, and NC hasn’t provided clear guidance.
BOTTOM LINE - Constructive Criticism from a Supporter
I love Home Assistant and NabuCasa. I own four pieces of their hardware specifically to support the project and because ZWA-2 set an incredibly high quality bar.
My criticism comes from a place of wanting NC to maintain that ZWA-2 standard across all products.
The technical arguments about Zigbee 4.0/Suzi are valid - you’re right that the tech isn’t ready today. But the product planning timeline that led to launching ZBT-2 one day after Zigbee 4.0 announcement was, in my view, a strategic misstep.
More importantly, the day-one integration and stability issues represent a quality regression vs ZWA-2, and that’s concerning regardless of Zigbee version support or baud rate improvements.
I’m confident NC will address the software issues through updates. But I hope they’ll also reconsider their product cycle planning to avoid similar timing problems with future releases.
ZWA-2 will be #1 for years because it shipped with complete, mature spec support AND flawless HA integration. I wish ZBT-2 had been given the development time to achieve the same standard.