Most decent tuners can give you a hand held unit to put the car back to standard and also give you the option of two selectable maps 
Wooow there one cotton-picking-second !!!
Doc, you saying that you have handheld units for sale that your customers can buy to swap maps?
Didnt know YOU were doing these too. 
Tell us more Mr The Doc
I was being good as a moderator - not a forum sponsor but now that my company is a forum sponsor.....
We sell a very reliable product that we buy in that can hold your stock map and two modded maps - you could have say a a day to day power map and a high RON map for example.
I'm a little up the wall at the mo but I'll take a photo of one later and pop it up
