To clarify - I've been able to remove them as well. As for the sock, perhaps trimming a hole in the sock?
More lucky than I was then... my screw head is all rounded and I don't see how I could ever get it out. ( I mean except drilling it out) I just ordered some heaters from aliexpress, I will try my luck.. yep a hole in the socket would work I guess. It's just not "clean". That said I definetely wouldn't mind if you were a chinese company selling hotends for 5$. I wish you'd have a few undersized block to fit the undersized heaters. Sorry for the pics they are a bit soft or out of focus also I used the block before the socket... and btw thank you for all the good work, except for this little defect they do work pretty well.
I don't use the provided screws for clamping the heaters. I had similar problems, the are really soft and the fit is not very good with an allen key... So I am using hex cap screws now which works pretty well, you can easily remove burned filament if you do not use socks or sand them and the just use a normal wrench wich can transfer more force on the screw...
I've been meaning to find a non-magnetic replacement for it, I had one model where I wanted to print in place some RE magnets but the screw made it impossible.