Always, after all theres more to a car than service history, mechanical condition, age milage etc.
Things like how comfy the seats are, positioning of controls, the general feel of it on the road etc are things i'd like to know before buying.
Good example is when i was looking for my first car, among others there was a pug 206 (which i was kinda meh about anyway due to being a pug but my price range kinda limited options) and jesus the gearbox had been raked, there was so much play in the stick you couldnt tell what gear you were in.
Now that was condition, but what would apply even if it had been brand new was the fact the pedals were so damn close together i couldnt use the brake without standing on my left foot, and there was no position to put the seat in to make it comfy.
As for dealers, ive not had any issues so far, hell the last test drive i had he just handed me the keys and went back to the office.