fellow RS3 owner, i am running apr plus on mine as i wanted to maintain some semblance of warranty. has already paid for itself as audi TD1 me over tune for the water pump. i have full stage 1+ bolt ons. amazing car.
i also recently picked up a b8.5 2.0T Q5 for long trips / dog hauling / bad weather. initially ruled out the 2.0 because: slow. i could not find a 3.0 nearby at a reasonable price so settled on the 2.0 with the idea of just throwing a tune on it. no intention of going down the rabbit hole of hardware mods so stage 1 was pretty much it. my other requirement was ability change fuel programs as i occasionally travel in states that only have 91.
i made a cost breakdown analysis of all the major EA888 tuners i could find - apr, unitronic, integrated engineering, and 034 motorsport including the tune cost with program switching and any dealer fee / tune at home kit. my local apr dealer charges $50 for a flash.
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with their 25% off black friday sale, 034 ended up being the cheapest route. got the kit and found out the hard way 034 motorsports tunes do not support the b8.5 flex fuel 2.0, so had to return it. that led me to revisit my list and look at what each tuner specifies in regards to e85 / flex fuel. 034 is completely out (they said it is under development), IE and unitronic make no mention of it. that pretty much leaves only APR.
i got tune last week. $100 add on for program switching. with cruise stalk i can select 93, 91, 100, or stock. all programs include complete flex fuel, i can run e85 or a blend. throttle response is night and day different for the better as is torque per the butt dyno. highway gas mileage is as good as stock. definitely no longer feels slow. i haven't even tried ethanol yet as it's pretty cold here right now.
this is my 3rd APR tuned vehicle and i'm very satisfied. i'm not loyal to the brand at all and know unitronic is the more loved tuner but seems to be APR is the only one on the ball here.
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