The T31 is tiny - I've been in one and I only just fitted in. I'm under 5'6". If a Cadet flight can be two strapping people weighing almost 100kg each with parachute then a T31 isn't the ship to use.
I've flown a K13 and a Grob similar to a Viking, as I learnt on glass I found the Viking easier to land.
If you are worrying about broken ships you should be worrying about crashworthiness and all the glass ships knock spots of the older ones in that respect.
And if you can bear to read back through the thread someone, sometime posted that a T31 (& presumably T21) wouldn't be a cheap ship to make these days.