Waiting at the garage or dropping it off, what's less painful?

[julioboyd]

Bit of a mundane question but I'm due for a service on my Q5 and I can't decide whether to sit and wait or leave the car for the day. The last place I went to had me hanging around for nearly four hours with terrible coffee, so this time I'd like to plan properly. A few people have said good things about Elite Audi Care garage and that they're reasonably quick, but I've no idea whether they let you wait on site or prefer you to come back later, and I'd rather not turn up expecting to hang around if that's not how they work. Also, if you leave the car, do they actually finish it the same day or does it end up being an overnight thing? I only ask because I have one car and no backup, so a surprise second day would be a real headache.