Hey great question! I think @jrperry, @stu1811 and @kendrosg nailed most of the reasons and know more than me about the intricacies of Home Assistant so definitely take their comments with open arms.
I’ll give you my perspective if that’s ok – Z-Wave is going to be very difficult to source for the next year or so. We’ve been told by both manufacturers that we shouldn’t even think about 700 Series at this point and to start preparing for 800 series in 2023. Our current switches run on 500 Series, which has slightly better sourcing than the 700 Series and we will have limited supply all throughout 2022. In other words, 2022 is going to be a very tough year for us with Z-Wave.
So, if you have 10 or so switches left to finish your build and are happy with Z-Wave, then I would say stick with Z-Wave and buy the Red Series. However, if you have a much larger build and/or don’t feel like buying the remainder of your build all at once, then I would consider the Blue Series as we will not have these problems sourcing ZigBee chips.
From a features perspective, the switches are basically identical. The great news is that we were able to replicate all the favorite features of the Red Series with ZigBee (something I was very nervous about) in that you will have scene control, notifications, energy monitoring, etc.
From a hardware side, really the only difference is that there are no heat sink tabs (which make it easy to install), it’s slightly slimmer, and you won’t have to worry anymore about purchasing separate SKU’s for On/Off and Dimming.
Our beta testers are currently running HA and we’ve been actively testing against that platform, so I’m hoping by the time the switches are released, all the kinks will be worked out with HA.
Hope this helps and gives a better perspective of some of the pros/cons to waiting as well as what we’re up against from a supplier side to help you decide whether to stick with Red or move to Blue 