Assuming you mean miles - i've just about done that. I did about 10k in the Polo (with a combination mk1 and mk2) and about 7k in the TT (again both mk1 and mk2).

No big problems yet, although the unit is at empeg for repair!

Paul.

Paul Haigh, Reg. 4120
(mk1) 6GB, Blue, 00254
(mk2) 12GB, Red, 00357