Review on Enhanced Neiko 10181A Titanium Grooved 3-Piece Set by Steve Jones

I purchased this step drill bit to drill a 7/8" diameter hole in 28" stainless steel sheet metal. cutting oils. The chisel cut to 9/16" and didn't cut to 5/8"! I sent it back for a replacement and with the new one I started with a 1/4" pilot hole, it went through the stage fine until I reached the 5/8" stage and stopped and pierced again. I used small step drill bits to drill pilot holes and they worked fine with no problems. I think they're disposable bits, but for big holes they're useless, at least my experience with stainless steel. It's really thin material and the drill had to go through it.