remap 159 with galletto myself?

Hi, I drive a 159 1.9JTD 8V.

I'm considering remapping it with a "galletto 1250" tool myself:

Galletto 12.50 flashtool

Advantage is that I ca rewrite the original file when returning it (lease vehicle).

Does anyone have experience with this? And does anyone know if the supplied tuning profiles (with the Galletto) are ok?

thanks