I've bought a lot from DrivethruRPG over the years. Like, a lot.
Have I had problems? Sometimes. I always say that the packing on the POD could be better. Any damages are quickly rectified though and a new print sent out.
The choice, especially between the different store fronts such as DMs Guild and Storytellers Vault, is immense and puts any other merchant to shame. Just the classic D&D I've got from here would be enough to blow my mind.
Really. I can't appreciate this company enough.
Disclaimer. I have stuff up on DTRPG and DMs Guild for sale. The customer service from that side is terrific too.