I have a remapped Leon TDI FR.
Jabbasport are well known for being "enthusiastic" with their figures - what counts is that you are happy with the performance, and you will be.
Things to note:
1) Tyres. When remapped your torque will be knocking on the door of 300lb ft, expect heavy tyre wear. Mine lasted 14k, but to be honest they were shot at 12, and that's with a remap at 5k.
2) Clutch Slip. Under 10 degrees c the clutch will slip between 2k and 2.8k rpm, colder=more slip, because the torque will increase. Unless Jabbasport factor this in and drop the boost accordingly, expect it. First day of the year today I can remember being over 10 deg c and I got no clutch slip at all for the first time.
3) Smoke. It will smoke more. Stock=low/no smoke. Remapped+warm weather = smokescreen behind you.
4) Wheelspin. Don't expect fantastic 0-60 figures. You have to be careful on the power in 1st 2 gears or the traction control will go mad and you won't go anywhere. Turn off traction control and you'll pretty much just sit there at anything over half throttle
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Mine wheelspins up to around 50mph unless I'm careful.
5) Fuel Consumption - I've not noticed any difference in day to day. On longer runs, fuel consumption seems to be slightly better. Driving miss daisy I can get 530 miles on a tank then reserve light on. Driving normally somewhere around 450. Caning it, somewhere around 380.
Other than that, when remapped and on the move you'll generally stay with similar size cars up to around 230hp, so stock Impreza WRX, Porsche Boxter Non S, Merc 3.2 SLK etc, at least up to a certain speed (I don't know, all of those, we ran out of *private* road cough etc) - in other words perfomance is pretty good for a practical economical car, though a remapped Cupra R will show you a clean set o heels
In other words, I think you'll be happy with it
I wanted mine remapping after 1500 miles - stock 150hp really isn't quick at all, but once remapped it removed the urge to instantly trade it in for something with more oomph (though I want a 3.0d Beemer next, or something similar).
Hope that helps.
Enjoy!