Stock rollers/aftermarket cam

I know Brian at IMM sells a set of drop in roller lifters for the LA, which is what i thought i would need...but basically, as long as the stock roller lifters are working ok and are in good shape, i can reuse them with whatever hydraulic roller i choose? is it recommended that i replace the lifters upon rebuilding the engine, even if i just replace with stock replacement style ones? im just wondering what makes one type of roller lifter better than the other to warrant buying aftermarket ones

thanks!