I am going to jump in here as being a Chevy, Buick, GMC, Cadillac deal that has the required Cobalt and switched on a dealer.com site in April of 2011. We made the jump after a lot, and I mean a lot of research and a lot of conversation with many providers. In the end I picked dealer.com because I felt like they could deliver. I am not going to knock Cobalt, its a good product, but it was felt we had maxed our potential with the required site.
Our dealer.com site is generating about 45% more visits than our Cobalt site did! In the first month, we doubled sales through our BDC. I took our Cobalt site to bare bones, concentrating on the DC site, and there are still lots of things to be done. I really like how we have more control! Our web site form leads for 2011 decreased by 8%, but our shows increased by 180% over 2010. We got less leads, but we got better quality leads. We did add an additional person to the BDC and put in some tight monitoring and tracking. But I can tell you for sure we saw a significant change in 1 month with making a switch with the quality of leads and the closing ratio!
I hope that helps. As stated; it is what you put into it. I had great reps over at Cobalt, I worked that site weekly. It was a big leap, but it's been worth it so far.