anyone use a comp roller cam and lifters in LA small block

Are you asking about solid or hydraulic rollers.

Shouldn't need to bush with the new hydraulic rollers unless something is seriously out of whack. The lifter bodies are tall enough to shroud the oil holes through full lift on most cams. There's another trick or two to avoid requiring bushing the lifter bores/unshrouding.

As far as direct drop in. No way in hell were the comp hyd. rollers going to fit in my 360 roller block. The valley needed to be ground to clear the tie bar on the "Drop in Retro-fit Rollers". Of course the short block was already put together. Disassembly to grind, rewash and re-assemble was out of the question for me when alternatives were available. I ended up getting the stock MP rollers, spiders and dogbones.