sampled... or tweaked factory sounds... That question actually depends of what hardware/software you're using, but all in all... I prefer sampled or tweaked sounds since it has more personality
most of those "factory" drums are sampled. in fact im sure probably at least 80% are, because compared to going out and recording hundreds of different drumsets in different enviornments, or completely synthesizing each drum from scratch, sampling is way cheaper, more effective, and gives better results. so bassically the difference between buying a bangin beatz set or buyin some vinyl and sampling it yourself changes your sound very little if any in the end. i'm totally down with finding all your own drums on some old soul and rock records, thats the pure shit, but i gotta admit there is no difference in the drums you will find on bangin beatz or samplecraze or similar sites
Both have their place in my production. It depends on the kind of track I am doing. Although, I love to sample my own drums. That's one of the fun parts of putting a beat together from scratch.
I use both factory and sample drums. It give you more options. Plus, you get to creat on top of those factory ones. I EQ, add EFX. I also recorded my own. I've used Boxes, Buckets, Pots, and even my daughter toy box. You be surprise at what sound you can create with things around your house.