As a carpenter, I’ve used dozens of different magnetic bit holders for screwguns. I find that Jack Rabbit Tools’ Mag ring is a great alternative. It’s a brass ring with embedded magnets that slips onto any 1/4″ drive bit.
It solves two problems with most magnetic tips: clearance and bit retention. In tight spaces or recesses, a bit holder can be too wide, and prevent access to the screw. Bit retention can be a big problem, especially with square drive and Torx fasteners, as the bit sticks in the screw head, and is pulled out of the bit holder. It doesn’t always stay in the screw though, and may fall into a hard to reach spot, or necessitate a trip back down the ladder.
The Mag ring works on any 1/4″ bit, round or hex shank, placing 3 rare earth magnets against the shaft. This lets you use a bit mounted securely in the chuck of your drill or impact driver. The strength of the magnets is far above average, holding fairly large wood screws easily. As powerful as any holder I’ve tried without a magnet in direct contact with the screw head. The advantages of the mag ring almost always outweigh ultimate magnet hold for me though.
I’ve been using them for about 5 years, The small size has led to losing a couple, but haven’t had one break or wear out.