Which ones? Sold by the 3rd party, or those sold by Amazon who have price matched?
These are fakes
Woukdnt work with my bosch 12v driver, not enough torque in it i guess but with my 12 impact driver it worked fine, cuts through on its own no need to push them
The negative reviews makes me wonder if some fakes have got in the supply. Had these bits for years and commented on the last one how good they were. The only time I studied with them was when the battery was running out. With a fresh battery they go through joists in seconds. I must admit the bite has caught me off guard in the past and ended up with a sore wrist for a few days. Can't say that I've ever had them wonder either whilst drilling always go through straight and clean.
Make sure to clamp your timber down well or it'll spin like a helicopter that's lost its tail rotor. :S