Pros
This is the 3rd motor company I've worked for (Pendragon/Lithia, then Marshall Motor Group), and it's the best by far!
With the right manager above you, you can go far, and the opportunities don't stop. I've been with the company for almost 8 months, and I'm now on my 2nd internal promotion, something I've never been able to do in previous places of work.
Everyone, both on-site with you or at external sites, genuinely seems to want to work together; there's very little animosity, and you can build relationships very quickly with coworkers.
Cons
The money could be better, and some form of CBS-incentive scheme wouldn't go amiss, but they're minimal issues.