I'm not familiar with the merits (or otherwise) of a 455 vs a 377, but I pass on 222s (Meridians) and wait for HSTs on the MML when I can - mind you these days I know the timetable well enough to only turn up for HSTs (and occasionally get a nasty surprise when a 222 shows up!)
I suppose there perhaps is a bit of 'train snobbery' in all of us. For example, I too will time my journey so that I end up on a HST as opposed to a voyager if using XC to travel home from uni.
But if I turned up at the station with a certain time to travel in mind and not like the look of my train so wait for the next one? No chance!
On reflection then, I'm more of a 'planned train snob'
The 2009 Stock on the Victoria line I also try to avoid, I used the Vic all the time when it had 1967 Stock as they were my favourites, but the new 2009 Stock is awful in my eyes, terrible seats and it's far too hot on them.
Good luck with that, it's been all 09 stock on the Vic for a while. Seats are less comfortable but a) how often do you get seat on the Vic and b) no-one's on the line for that long!