I have recently purchased a B8 S4 S-tronic with the 3.0 supercharged engine and I'm loving it so far

I have a few questions which I hope you guys can help with:
How easy it it to remove the spot welded tips that are beyond cleaning as I want to replace for shiny new ones?
Howdo you find the MRC stage 1 and 2 remaps and pully (for S2) as I'm looking for more power in the not to distant future?
Have any of you has the s-tronic remap and what difference does it make?
Thanks
Mat