Yes the rife is very very jiggly to say the least. The ride on the Renatus units seems worse than a regular 321. I wonder if it has to do with the extra weight they have to carry around. The interiors are very bright and clean though. Maybe a bit sterile ..almost akin to a dentist surgery. The whine of the traction system reminds me of the dentists drill. Around 75 and 80mph there was a particularly nasty resonance.
I really don't like the Renatus 321s, they look more modern but they have numerous flaws.
I have never had such a rough ride in my almost 20 years of using the GEML as I have on them. Honestly it was so bad that I've seen multiple coffees and phones and stuff on tables go flying in ways I have never seen before. Someone ahead of me put was trying to work on their laptop, but wisely decided it might not be the best idea if they want their laptop to survive the trip. The banging from underneath the train on the most rough riding parts where the train lurched up and down and heavily left and right was the only time I have been a little worried on a train about a potential derailment.
Then you have the broken air conditioning, creating a sauna, with no working Wifi, a PIS that had issues and blocked off plug sockets and every rattle and squeak under the sun in an overly bright environment. It might look more modern, but once again, in typical Abellio fashion, it's style and marketing over substance.
But jumping straight out of a 321 and into a MK3 coach reminds you how good the MK3's are - even if the interiors now are way past their best looks and comfort wise!
I'd place the Renatus 321s right at the bottom of the ride quality ranks on the GEML, they don't touch a 321 that hasn't been refurbished, let alone a 360 which trumps both types of 321.