Questions from a novice...GTS Premium?

My first post and probably a couple of stupid questions from a novice - but all thought and help much appreciated!

By way of background, I am in the market for a Dino and have been doing a great deal of research: talking to owners, dealers, finding a huge amount to read on websites like this one - very helpful btw. I have read Mattias's book from cover to cover and checked out cars sold and advertised in the UK and abroad. I have looked at probably 20 cars (mostly in for a service and a really good opportunity to poke around and see the varying levels of quality out there). I have driven and been driven in different cars and am now getting very serious about a couple currently on the market.

My problem is, the more I think I know, the more I feel adrift! When the cars were sub £80k (and of course even lower before that) it wasn't such a tough call......but the prices demanded now require serious thought. I don't mind paying £5k over the odds buying from a dealer with a reputation to protect.....but I really don't want to get mugged.....and some people are asking daft money for decidedly imperfect cars. So...

Q1: I had always thought that there was a premium for a GTS over a GT...but at least one person has suggested that this isn't the case and prices simply depend on quality and timing of sale: your thoughts?

Q2: There does seem to be quite a difference in the way different cars drive: some older and less recently restored cars seem much 'slicker' than at least one I have driven that had only been restored 5 years ago: would you go for the car that looks technically better on paper, or the one that simply seems to drive better.....tough question, but is the general feeing that there are simply good and bad cars out there?

Q3: Just how important is a car's history? Specifically, if a car has been restored in the last 10-15 years by a reputable specialist, should one worry about there being a lack of history before that?

Q4: just how lucky do you feel if you bought your car several years ago and the stakes were a little lower?!

Would appreciate any feedback and thoughts. It's a big decision to dive in and buy a Dino and while it is always going to be a heart-driven decision, I am trying to at least give my head a chance to get round the maths.

All the best.