just that they're very much an unknown
what's their history of VAG cars, how long have they been doing it, where do the files come from, what experience do the tuners have, when editting the file to 'dumb it down' what are they actually doing, can you adjust it for different fuels, poor weather,
dealership trips, security features
this is all stuff to consider, not just whether it'll make the car fast
eg, Revo & APR will have mapped 000's of VW group cars each - how many have emaps done.... what proof of reliability is there
I'm not saying it's a poor product, but the first I read of them was when Si got it done.... and that was their first LCR. can't have been more than 3 months ago.
Your money, your choice, but like I said, there's more to a product than how cheap it is