I don't think they care all that much, but you may not have the ability to wait inside depending on location. You likely won't gain anything more from being there that early. It may be better to just take that time to practice what you think your weak points are.

My spouse just got their license from the West Oak Lane location. The test took about 5-10 minutes. You'll parallel park in a generous space, exit the parking lot, cross the road, go around a couple neighborhood blocks, and come back. It's not too hard at all. You got it!