Chapman works great for me. I doubt you could break one or twist it off. I only needed 3 bits to take apart any Pietta, Colt or Uberti I own, so I didn't even get the set.
Just the 3 bits..... CM89, 90 and 93. A buck-thirty each.
http://www.chapmanmfg.com/OrderParts.html
I'd buy the handle, extension and even the ratchet if I was ordering all over again. But I just use the bits in standard hex head screwdriver handles that I already have and they work pretty good that way.
(Some screwdriver handles have a shallower socket for the bit than others. Chapman bits are longer than standard tips)
I did go through two sets of Wheeler "gunsmithing" screwdrivers. Whittle you some out of wood before you buy those. They'll last longer and be harder to twist off than the Wheelers.
