Right i thought id post this up as to end all the confusion as to whether it will/wont fit on 172s and not just Cups.
I have spoken to Nick at Hillpower and he has confirmed that a RSport ECU will work with a standard 172Mk2. To get this to work, he has to order the ECU in for you after you provide him with your Engine number. This is located neat the dip stick.
Im seriously considering purchasing one at the moment, we all know that it voids the warranty but with it being a 15/20 min job or removing and replacing, im not that concerned.
The price is roughly £260 fitted last time i got a price list from Hillpower.
Please dont turn this into a slanging match saying the RSport is crap etc what you want is a unichip ..... etc.
I posted this as an informative post as there is still some confusion that they cant work in a Standard 172.
Kev