I've been comparing 7mm magnetic sockets and nut setters for use with a drill/driver (not impact) before commiting to a full set. Task is removing and refitting car interior trim.
PB Swiss = Switzerland. (Impact rated unknown).
Grey Pneumatic = Taiwan. (Impact rated).
Erbauer = China. (Impact rated).
Britool Expert = Unknown (probably China or Taiwan). (Impact rated unknown).
Visual observations.
Erbauer has thicker walls than the other sockets which may provide more strength for impact use but may cause issues when access is limited. Expert and Erbauer have larger magnets than the PB and GP.
The finish on the PB is impeccable. The hex on the Expert looks to be off centre so the socket wall is not the same thickness all round. GP and Erbauer are just fine.
While the three nut setters each have static magnets the magnet in the Grey Pneumatic socket is mounted on a spring and can be pushed in about 23mm.
Observations while using the sockets.
All four sockets can hold a screw when fitting parts.
I found that the magnets in the GP and PB were not strong enough to retain a screw when removing parts. The screw would mostly stay in the dashboard. The GP was the worst at holding onto screws.
I found that the Erbauer has the strongest magnet so was the most useful for my task. It's thicker walls did not cause any clearance issues. The Expert also has a similarly strong magnet but was over twice the price and offered no clear advantages. As far as I am aware Erbauer do not offer a complete set.
It is not my intention to bad mouth GP. I know they are popular here. They may be far superior at other tasks and I think the larger GP sockets have larger magnets. This was just a little experiment.