Good drill bit sharpener - Help I'm dull

[Jet-Stream]

I maintain my several washes and do installs, so I am constantly drilling holes - often in stubborn stainless.
I would like to find a good drill bit sharpener that works on a variety of sizes.
I've tried two older models from black and decker that didn't work well. I do ok with 1/4 - 7/16 on a bench grinder.
Anyway, does anyone have any recommenations? Does the Drill Doctor work well? If so which model?

 

[I.B. Washincars]

I've had a DD for years and it works great. I'm not sure of the model, but it will go up to 3/4". It does not look like the ones that I see advertised as of late.

 

[Red Baron]

I got a Drill Doctor last year with proceeds from my Fathers Day Home Depot gift card. It's such a pain in the butt to use, I don't use it. Ever. I find it easier and faster to buy the el cheapo bits and throw them away when dull. Drill slow, use oil, they'll last awhile.

In a bind I have found that I can often get one more hole out of a bit if I angle the bit against the concrete and turn it on high to give it an edge.

 

[MEP001]

I buy cobalt bits, usually 6 1/8" bits at a time, and use those for starting holes which I enlarge with a step bit. I can get a couple hundred holes drilled in stainless with one 1/8" bit.

 

[Earl Weiss]

Use the drill doctor. Typicaly do several bits at a time . Surprised how well it works.
Always use cobalt bits.