Not at all. There's a reason they're so unpopular, and that's because they're like £15,000 more than a TTS. They're exactly the same car, except the RS has around 60 bhp more (0-60 just under 1 second less which isn't a lot of difference). With a re-map for a couple of hundred ££ I could get it to near that.
Oh, and the RS has a static spoiler, whereas the TTS has a moving spoiler. I think only an idiot would pay that much for such little difference.. might as well just get a Gallardo!