Irwin - Speedbor (Rating: 5)

I picked up the 5-piece set of these from Lowes yesterday to drill holes to run wires through floor joists. I'll be comparing these to the last ones I had which came in a catch-all bit kit I got for Christmas years ago (they sucked).

The bits bored fast. I mean really fast. I'm not sure what difference in the design that makes them bore so quickly, but it definitely made the difference. I used the 5/8" to bore through the joists at a slight angle (since I didn't have a 90* drill). Holes went through relatively clean with a little tear out on the back end. I'm sure if I clamped a sacrificial scrap on the other side, it would have been clean through.

There was a little bump about halfway through one joist as my hand slipped a little on the drill. But that was my fault and not the bit. The bit kept going through despite the bump.

I'll probably never give up my forstners, but for $8 I'd say these are a good deal to add to the shop.
~DB