Looking for a Change

Hi.  I'm looking to swap my Derv vRS in the Summer, and out of a list of alternatives, I'm edging towards a TSI vRS, around two years old.  

I have heard some horror stories about them, and I have seen that others get no problems at all.   My new car will need to last me at least four or five years, and I'll only have a year (at most) warranty as a back up should anything go wrong.

Is there anything in particular I need to look for when I'm looking around and test driving, and do I find one with as little mileage as possible, or do I get one that has covered 40k miles and had a DSG service, or...?

Thanks in advance for any advice!