the VO fenders come pre drilled and are complete set now. Once you cut the stays, it should be pretty easy. If you've never had fenders before, fenders stays are pretty beefy.

I think the VO fenders are easier to install than SKS fenders. However, I like SKS fenders for commuting more. Since it's plastic, it weighs a bit lighter, more durable, and I care less about it. The VO fenders are really nice quality, and probably something I would put on a C&V type of bike.