[captain harlock]

Actually, there are two types of bearings used in the supermaxx:
The ones most people use are the 8x16x5mm and the ones used with the six mm axles are the 6x16x5mm.
Almost all buggies and truggies uses the 8x16x5mm bearings. I did not go for it, simply because I thought that the 6x16x5 incorporates larger balls and thus, they are more corrosion resistant.
I think the 8x16x5 ones has smaller balls.