mines a 100shot twisted sanity kit/purge kit with progressive controller
iv set it to come on at 10% and progresses through to 40% @end of the revs (prolly going to change to a 50shot soon due to me never useing over 40)
on my old k03 turbo the highest i ever ran it was at 10~80% on a RR (got 298bhp/309lbs on k03 with 80% nos) never had it RR's yet with nos and different turbo
make sure you plumb it all in right if your doing it yourself (id personally get someone who knows about it to install and set it up for you) iv seen 1 or 2 setup wrong now