The Wii came back from repair today, a bit earlier than I was expecting. It seems to be in good condition, no scratches or marks on the case, and is working ok so far.
Fingers crossed this one keeps on working. If I wanted to keep sending a console back to the repair centre I'd have bought an Xbox 360 !.
Just gave them another call and my Wii has now been entered into the system and is already with the repair centre so should be back early next week.