The stepped drill bit that comes with the kit is not the best thing in the world. It will be a major buzzkill if you are using it with a battery powered drill. A lesser buzzkill if you use it with a power drill. I bought a better version of it at Home Depot for around $40 and was very glad I did.
I found out with the very first hole that the step bit wasn't going to cut it. I had plenty of regular drill bits, so I chucked a 1/4" bit and drilled the required 1/4" holes and it made great pilot holes for the step drill bit. After starting with the 1/4" hole, the step bit did great.
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