Definitely try and go for someone that's been recommended or at least someone who you can complain to when things don't go your way (ie. something who doesn't look too rough :tongue.
Had some JCW side skirts done and painted in what was supposed to be Metallic Astro Black... at the time it looked like a perfect match but it's taken me a couple of weeks to realise that it's not quite the same..
...i know people reading this would start thinking that it's nigh impossible for a perfect match but the paint colour he used was more 'bluey' than 'blackey'... thankfully it's a close enough match and can't tell if you're standing next to it... you'd have to have your nose next to it for you to be able to tell....
Not bad considering how much i paid to have them painted and fitted. By the way, i paid £100 for it to be painted and fitted! Pretty good IMO.
Final thing to take away from my longish post is to inspect the paint work under direct sunlight if possible. Eyeballing in the shade won't reveal much unless it's completely the wrong colour!
£100 painted and fitted sounds good, was that from someone local like a bodyshop or was it a dealers? I would be a bit worried about the colour match as well to be honest, it would be nice to know where they get the DS paint from?