I really think they're not particularly better or worse than any other car - a ten year old car will have had any manufacturers niggles or shortcomings sorted out, so it's really down to how well it's been maintained and treated during its life. My 04 Stilo's build quality is certainly better than a 53 plate Fiesta that I had for my missus, and not significantly different from the VWs and BMWs I was used to driving.
Best thing to do is have a good look at it - has it got lots of little dinks and scratches that might indicate that it has been harshly treated? Is there any service history? Is it grubby? Has it had any extras like a flash stereo, speakers etc that might hint that it's been used by a "boy racer" - that might be giid if they've tweaked and loved it, or bad if they've hammered it...
Above all, buying a car is as much a decision of the heart as it is of the head. Do you like the look of it? Does it "feel" right? Do you have lots of doubts now, because once you've handed over the cash, it's too late. But always remember, it's a ten year old car, it isn;t going to be perfect.
