I installed a Kerma 2.0 tune a week ago. I liked the idea of being able to quickly reload the stock tune if I needed to take the car in for servicing. The tune was easy to load up, took all of maybe 10 minutes to load. But there are preliminaries that needed to be done. Download the stock tune info, email Kerma with the info, get the tune file from them, place it on the tune console, carry it out to the car, putz around with a not too difficult OBD2 plug, and load it up, and go burn a few miles of the right front tire. Since the tires are (IMO) crappy Continentals I'm wanting new tires soon. Is 30k miles too soon? The Continentals are noisy, worst tire for noise I've ever owned.
If you install a tune, make sure your battery is up to snuff! Everything comes on, including all the fans under the hood! The process was quite easy though. The car has quite a bit more power now than the stock tune judging by the seat of the pants feeling. Subjective, yes, but you WILL notice a difference. You won't need a dyno to tell you you've got more ponies under the hood. If I'm going to achieve my goal of better MPG I need to lay off the go-pedal. Damn! It's made the car more fun to drive, and I already love this car.
With the stock tune the car would easily spin the tires in first gear when the turbo kicked in, which seemed to lag for 1-2 seconds, but it seemed to lay down after shifting into 2nd gear (DSG). With this tune I can spin the tires in 2nd as well now, and a little spin in 3rd depending on the road surface. We have a lot of chip seal pavement around here. From a dead stop the turbo still has lag, but it kicks in much quicker than before. I didn't get the tune for the power, but you'd have to be nearly dead not to notice the increase in power.
My motivation for the tune was for some improvement in fuel mileage. With the stock tune, my MPG has hovered right around 37mpg in all around driving, a combined 40/60 city/highway. Best tank MPG to date is 39MPG. My bone-stock 2013 Jetta Premium (DSG) averaged 40.1 over 23k miles and 3.5 years of ownership. Average city/highway driving with the Golf is the same as the Jetta. I turned the Jetta in to VW in Dec 2016. I bought this Golf in Dec 2018. It's just broke in with 24k when I bought it. It's pushing 29k now. Since I'm about 250 miles to the next fuel-up I can only go by the numbers on the consumption computer readout until then. I've driven about 80 miles of the current tank with the stock tune, it would be great to see anything over 40mpg.
I've checked the real time and overall numbers on very flat and level highway at 64mph indicated, and 62 via GPS, a Garmin unit. Those numbers are showing me 52-58mpg on the instant readout, and 44.8 overall. Much improved! Before the tune the overall MPG was never in the 40's so I'm optimistic that I'll get into low 40's. That would be great. So far so good! The instant and overall MPG readings from the computer are encouraging.