Nitron helped me out last season on the DesmoDue racer, but we had to set the shock up once it was in the bike. I'm no expert so my mechanic (
www.louigimoto.co.uk) set it up - but when it was adjusted, boy was it fecking brilliant.
I'm on a different bike this year and have an Ohlins (just coz it was fitted already) and it's not as good as the Nitron. Last years bike handled awesomely - difference is, this year I have the power too

Not much help really, but basically, I don't think any shock will arrive 'set-up' - so you need to get someone who knows what they're doing, so help you set it up.