I'm fairly active over a number of VAG forums and TBH the number of instances if issues with remaps from any
tuner is fairly minimal and even those i can recall were sorted when the customer returned to the vendor.
To say that it is common for a REVO dealer to load the incorrect code for the specific ECU in the customers car is frankly utter tripe. If you know of any dealers that have done this perhaps you could let me know and i'll pass them on to Kev at REVO? REVO holds a database which the dealer searches for the correct code from the customers ECU part number. There's no lottery as to the code you will be given.
With regards the boost and timing settings for the code; once the correct code is on the ECU the boost and timing can be altered either via the dealers laptop or with an SPS3. I can see it is possible to set up a car incorrectly here, particularly if the customer uses crap 95ron fuel. But, the dealer will run the car up the road on full-load and should monitor the CF's and Boost Requested v's Actual via VAG-COM. The customers butt dyno will tell them if the car has been set up right and if they have any problems it would only take the dealer a few minutes to correct them.
Heatsoak is a problem on most single intercooler 1.8T's, just because the intercooler is so damn small. I get IAT's of 60degC+ in summer but using 99ron V-Power it still produced the power figures i quoted above on the stock intercooler. Oh, and it pulls all the way to 6000rpm with no significant timing pull.
More often than not, for any type of remap (not just REVO), if the customer is unhappy it is likely to be a fault with the car not a software problem. The increased boost pressure has a habit of highlighting weaknesses in the design of the 1.8T such the Diverter Valve or the boost hoses that become soft at the higher temps then brittle and split causing boost leaks that throw a fault code in the ECU. Annoying problems sure, but easily and cheaply rectified. Chances are the problem was there before the remap, simply that the extra power amplifies it.
Remapping from reputable code suppliers is, on the whole, a painless experience but also something that has a lot of myths and superstition surrounding it. Any customer considering it should go in to it with their eyes wide open.
Huge resources of info are available on many VAG forums such as:
REVO do a 5-hour free trial of their software, i'd thoroughly recommend it