I tried a simple resistor thingy a few years ago - more power for sure, but rough as, and lots of smoke.
I then tried a decent digital tuning box (car new, warranty considerations etc) and never felt the need to go for a re-map.
It was a great mod.
I recently fitted the now redundant tuning box to a mates A4, replacing another more simple resistor based box, and he's over the moon with it. More grunt, smoother, bigger smiles.
No doubt a proper re-map is better...but the tuning box is a decent compromise...and removable in a few mins, if required