Hi Cammy.
I've had a re-map done at Jeremy Fearn's and its great!
The RR feels very powerful and also relatively fast too!
Fuel economy wise I now get around 35-37mpg the worst i've seen since the re-map is 28mpg
I'm going to have Jeremy's bigger intercooler kit done and also change to fully synthetic oil (as per his recommendations!)
Cleaning the leather?
I've had loads of cars over the years with leather interiors and I found the best solution is to use Johnsons baby wipes on the leather to clean it, and then once the leather is cleaned I use leather conditioner to keep it from drying up (I do the same on our sofas too!)