I really like the second silver one. The only reason I don't like the last one as much is because of the pink. When coming up with the colors for our website we tried to make sure we wouldn't turn off any clients, so we chose colors that were neutral. Pinks and 'feminine' colors were not used. Not that they are bad, you just want to appeal to a wide range of clients.
I also really like the tag line. I think it is very professional and makes me want to know more about your company.