What I liked about Mainline was their immediate responsiveness. From my first email inquiry on inventory/availability and all subsequent contacts they were very good at responding - and very pleasant to deal with. They didn't have exactly what I wanted in inventory - nor did the other dealership I dealt with over the bridge in NJ - but the Mainline salesman quickly got back to me the same day after doing a search and he found what I wanted at the port in GA.
The salesman at the other dealership took a full week to get back to me on his search findings (after promising me he'd have it w/in 2 days), even with a couple of follow-up contacts by me to check in on status - each time giving me a lame excuse. It was kind of surprising since that was the place I went first - and in person to test drive, and I made it clear that I was ready to buy right away if he could find me the car specs I wanted. Might have just been the salesperson rather than the dealership (I'll give them the benefit of the doubt I guess), but was definitely a little ticked off with how it was handled.