drill bit selection

Didn't see the rest of your post.

Not qualified to comment on that part.

However, I have only bought one drill bit since I switched to cobalt about 3 years ago.

One.

1/8"

Because those just break from a bad drill angle.

Kind of hard to find cobalt, and they're about 2.5 times the price of "regular" bits.

...but as far as keeping an edge, they far outweigh getting new ones every few months.

I attempted to re-sharpen bits a few times...and learned that is not "for me".