Roller lifter retro fit, what cam?

If I used a hyd. roller lifter retro fit kit what cams would I use?
Normal flat taped hyd. cams or the hyd. roller cams?

I believe you must run a roller cam with roller lifters, and a flat-tappet cam with flat-tappet lifters.........................I suppose you could try running roller lifters on a cam designed for flat-tappet lifters, but I don't think it's recommended --- use each part for its intended use - hence, roller with roller, non-roller with non-roller.