Hi Katie,
With regards to your PM;
A quick low down of my experiances with an MR2 (DISCLAIMER: Also includes my opinion as an owner)
Well built cars as far as interior goes. I ripped mine appart to fit a 10" sub / 1100W rms amp with some components and found that everything is well held together so there isn't really much question on rattles unless someone has been abusing the car. With the stereo up the outside of the car doesn't rattle either, in fact you can barely hear the stereo from outside which is fantastic as it add's to privacy. MR's have a comfortable interior, I drive from London to Brighton a lot and never feel uncomfortable at all. I should also mention the driving position as it differs from what your probably used to. They are a 'lay on the floor' car. A real sporty feel and I grew well accustomed to this.
Exterior is good as these cars rarely rust. Window rubbers usually need replacing due to the age of the cars. I replaced the rear lights on mine and although it looks better I fear for the poor 3rd party build quality. If you ever go to look at one of these cars check all the lines of the bonnet and rear end. People crash MR2's as they are very poor to drive in the wet. They handle like a god in the dry but come the winter you have to pay attention to speed in the corners as you will (and this is no reflection on your driving) spin 180 degrees and wave to the traffic on the other side of the road.
Engines are good and strong. Keep them topped up with oil/coolant and water and they will out live c0ckroaches. I have 139k on mine and still starts every time on the button. I would bring your attention to repairs as cambelt changes and any work that requires engine to come out is very costly. General servicing is easy as the oil filter/sump plug are within easy reach.
Finally I would add I had a great time in my MR2 but these cars impractical and dangerous in the wet. If your happy with your skill as a driver, the two seats and (if your due one) a cambelt change (£450.00 for a rubber belt inc fitting) then I would say for a two seater car you can't really buy better. The alternatives in my opinion don't look as good/work as well as the MR2 (and yes I'm aware some people would kill me for saying that about the mx5).
Hope this all makes it a little clearer Katie. I can't comment on the GTI T just yet as I have had it barely a week and so far wouldn't count myself ready to say yay or nay (but its a yay
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