I've been using a 2018 Kickr for about 18 months now with no issues and am on Zwift 4-5 times a week. My setup is pretty simple, using an Apple TV and bluetooth connectivity only with my Kickr and Wahoo HR monitor (no cadence sensor or PM outside of the Kickr). The PM in the Kickr is definitely accurate enough for me. I primarily enter group ride events and the occassional race and workout in Zwift.
Like the OP I'm in my mid-50s and with Zwift have almost doubled my highest weekly mileage prior to this year. My only $0.02 is to spend enough within your means to ensure an experience that will keep you on the bike.