takes 5 minutes to figure out extras on the qc, it´s well documented,
and after that just back everything up and you can leech of your own qc if you need something specific again
having to build specific objects in hammer would be annoying and would look less excellent.
the texture would certainly somehow look gross and adding specifics to it (e.g. skull on blu oil-barrel) would be no fun
sure, learning how to model and unwrap/texture is a book of it´s own, but definately worth the hastle