I had a different experience with zha and feeling better with z2m. I also believe having separate containers for core and ZigBee stuff makes home assistant more resilient. When z2m fails, core is not impacted and vise versa.
– topic derailing off –
Back to main question, if you are new and just looking for adventure, 5 Dollar cc2531 usb dongle is also a good start, you can upgrade later on, again, if you are in doubt about ZigBee path. If you already made up your mind, go with one of the adviced options.
Correction(s) as it is not all about the hardware as compatibility and stability depend on the integrations:
ConBee 2 adapters are great when using deCONZ integration.
ConBee 2 adapters are good but not great when using ZHA integration.
ConBee 2 adapters are ok but experimental when used with Zigbee2MQTT.
Texas Instruments CC2652P/CC1352P adapters are great when using ZHA integration.
Texas Instruments CC2652P/CC1352P adapters are great when used with Zigbee2MQTT.
Texas Instruments CC2652P/CC1352P do not work at all in deCONZ integration.
Silicon Labs EFR32MG21/EFR32MG12 adapters are great when using ZHA integration.
Silicon Labs EFR32MG21/EFR32MG12 adapters are ok but experimental in Zigbee2MQTT.
Silicon Labs EFR32MG21/EFR32MG12 do not work at all in deCONZ integration.
Slightly off-topic but can add that only Silicon Labs and older TI adapters is supported in openHAB.
Note that CC2530 and CC2531 are no longer recommended by Zigbee2MQTT and ZHA developers. The argument that CC253x only cost $5 also no longer works now that CC2652P can be found for $11.
I can’t agree with regards to the Conbee 2 with DeConz vs ZHA considering there are devices that don’t work with DeConz yet do work with ZHA, plus ZHA is (in my opinion) easier to work with. DeConz feels clunky, the UI is rubbish. I started with DeConz but got sick of how bad the UI was and that some of my devices wouldnt pair, so swapped to ZHA