I agree with some of what the s2k said. It is very much a cruiser as it has a torquey V6 compared to a 4 banger that revs to 9000 (or whatever, I forget now as I haven't driven an S2k for a while) As bronzee points out above, a lot of the understeer is due to tyre choice.
2 clutches in 10k and bad consumption - somebodys driving style is questionable. There have been problems on some examples with clutches but it isn't very common. As for bad fuel consumption, what do you expect driving in the city or like a demon possessed? I get good consumption on mundane journeys, it does come down with pleasure driving though!
Build Quality? Yes, it wasn't as good as it could have been. There has been huge improvement with the '07 model though.
It all comes down to taste. I chose the Zed directly over the S2k as it suited me better having a 6 cylinder engine and all the creature comforts. The nail in the coffin was when my girlfriend mistook an MX5 for an S2k. That was it. Zed bought!
I wouldn't have considered the BMW. Not my taste at all!