Hmmmmm, they may be nice to drive, but I commute on the line every day almost end to end and have done so for about ten years.
The seats are the most uncomfortable when compared with those on the 170s, 365s, 380s and even refurbished 180s.
The luggage rack design is poor. A bar has been added across the waist height shelf, presumably to prevent items falling out. What this does in practice is severely restricted its use. In 10 years I never saw any large item fall out of a 170 rack.
Announcements. Sheesh. Passengers are now inundated with very loud announcements. At least 5 - sometimes more - before departures and at each intermediate station - "We are now approaching... Remember your luggage... Mind the gap... This is the train for... Calling at... If you see anything suspicious call...". The guard and the catering service also chip in at the beginning and during the journey. So if you liked a snooze then you're out of luck or to even listen to something will probably now give you tinnitus. I don't believe that for the majority of passengers this number of announcements is necessary or useful.
Had my first run on one of these yesterday, and as an interesting comparison had 385s out and 365s back.
My observations would be:
Seats: the thicker seat base cushions make a huge difference compared to the Fainsa seats in the 387s and 700s. ScotRail's use of a high quality moquette (rather than the low quality stuff GTR and GWR use) also makes a difference. Definite improvement over other recent new trains.
Ride: average. Noticeably rougher and "busier" than the 365.
Windows: there is an awful lot of plastic panelling internally. There are areas where there is one small and one large window and a huge amount of bare wall, where there should have been two large windows fitted. Seat/window alignment is also poor. Not strictly window related, but there are also seem to be big equipment cabinets in the passenger accommodation which waste space and are much more obtrusive than other stock - almost felt like you could have put a normal/small toilet in place of some of them.
Overall, they are OK. A fairly average new train. They certainly don't have the "wow" factor that I noticed when I first got on a 380. As a direct comparison, the 380 is a far superior train.