I have used the Elite Suito for just under two months now and had no significant issues with the device. In response to the spin down comment, I could never calibrate the device with Zwift but by using the (painfully awful) Elite my-training app, I could perform a spin down and the device would save the calibration.
The Suito now appears to be knackered - I now find that it ramps up the resistance like it has a mind of its own. I went to enter a Zwift race and, even during the warmup at the start, the device went from next to no resistance to over 400w, all the time whilst making noises to suggest that the resistance was jumping all over the place (the same noises that occur when the device is first switched on and it, perhaps, calibrates itself). Having stopped pedalling, the device dropped the resistance off. When starting pedalling again, it would do the same. Almost like the reverse of ERG mode. This happens regardless of the gradient, or the power that’s required using Zwift. I was able to reproduce this same malfunctioning using sufferfest, the Elite my-training app, and with my Wahoo Element connected to the trainer in passive mode. Bizaarely, when the wahoo is connected to the trainer with a target wattage, the Suito behaves as expected. Power cycling all devices, changing devices (from my iMac, iPad, iPhone, wahoo) all generate the same glitchy behaviour.
I hope I’m not alone and there’s a simple solution out there, something that I have overlooked. I have reached out to Elite for their thoughts but thought I’d share in case there was anyone else out there, or someone who knows something I’ve not tried?