I drive a small, but very solidly built car, a Merc, with a top speed governed at 155. I don't get anywhere neat that but the acceleration has got me out of trouble from idiot drivers a few times - strangly enough either Golf or Volvo drivers.  It has room for two smallish suitcases, which is all you need unless you pack the kitchen sink or are going for more than a couple of weeks.

The Cavalier and the Carlton (had both) were rust buckets and although nice when new were heaps of junk after a very few years. My previous Merc was over 18 years old when I got rid of it and still very driveable and in not bad condition.  It never failed an MOT, wasn't particularly well looked after and very often went over 65 miles an hour in fact it spent most of it's like cruising on motorways at 70-80, so I don't really think you can generalise.

Vehicles these days are meant to break up on impact - it absorbs the impact better - just look at F1 cars they shatter almost, but like modern cars have a reinforced passenger safety cage - when was the last person killed or really seriously injured in F1 at speeds well in excess of 100 mph?

It's not the cars that are at fault IMHO it's the drivers.