I've got a feeling Clarkson is a 2nd username for someone already a member...?
Welshy may well find this stuff better than standard kit bits, and they may well be, I for one like hearing about mods people make
Even though I haven't git my Tam anymore!
BUT I think we should refrain from calling the Tamiya bits substandard in this case, their diff's are perfectly ok as kit, they don't slip too much and there's nothing wrong with the screw etc! Otherwise people may go out and buy these bits unnecessarily!