Last time I was on a turbo was Cosham to Southampton, The aircon was broken in the coach I was in, and the guard tried to open the hopper windows but they were jammed. She mumbled something about how knackered all the trains on that line were, and said that one of the other coaches had slightly better aircon. I wasn't too hot so I stayed put, but then when we were just about to depart Fareham, the ear-splitting door close beeps carried on going after the doors had closed and the train had left, and I ended up getting the guard, and it wasn't until about Woolston that the issue was sorted, but the door was locked out of use.
By contrast I was on a 158 from Barnham to Southampton yesterday, aircon was just right, and although we were held up by a late stopper, the ambiance inside those units is so lovely that I didn't mind too much. The only thing, of course, is that loading and unloading on a 2-car 158 takes an eternity!