I bought some today from Hein-Gericke, when I got home and looked at them the Heat Controller (the newer push button one) had bits of plastic missing around the edges.
Took it back and exchanged it, the replacement has a similar thing, the plastic is way to brittle
It would seem Oxford has a quality issue as I will be taking it back tomorrow for a refund.
Shame because the grips look very well made but the control box just falls to bits.
Edit: I've emailed Oxford the photos I've took and will post back their reply if any.
The oxford heated grips are the best grips i've fitted to a bike. Granted the unit isn't the strongest but they are fan-tastic!!
See if you can get the older oxford grips with the twisty dial.