Ok , now I’ve been I can make an informed(ish) opinion. A 120mm bike will be fine on the blue and red trails with an average rider , if you’re a good rider then with care the red/black trail(black powder trail) would be rideable , We didn’t ride the double black as we were told some of the corners were a bit dicey due to the ice on them so I couldn’t comment on it.
The Youtube video’s really do no justice at all to the trails they’re all much rougher than they appear on film , we had a great day and will definitely back in the future. I loved the red/black run although I couldn’t manage to get a decent line into the first tight left hand switchback .I ache like a bugger today but am still buzzing after my visit , the only downer was the traffic driving home from the start of the M56 till the other side of Manchester was a bit of a car park most of the time.