Having a smart trainer and not using erg would be waste of money for me. That exactly has been my case so I sold my kickr and bought Elite Quick Motion Rollers with 3 Resistance levels
Very happy with the decision. The workouts are much more challenging (keeping up with the power demands of the workout!), demanding (balance), rewarding (felt muscle soreness as different muscles are being trained than on a fixed trainer)… and more fun.
Additionally:
I dont have to manipulate my bike. Just put it on the rollers and go…