I wouldn't shy away from a SP1, especially if you're more of a casual sport rider vs. a track guy. You can get a smoking deal on one because everyone has a boner for the sp2. Dig around a little and compare some dyno charts stock vs. stock there just isn't a whole lot of difference, and if you prefer a sp2 swingarm thats an easy fix. I have a sp2, honestly I think the sp1 swinger looks better but I'm a old school 900rr guy and they look similar. Also the wheels on the sp2 are lighter but you have to ask
1) how much money do you want to spend and
2) are the upgrades worth the difference to you. Basically the point is unless you're Ricky Racer you probably won't even ride a sp1 to it's limit so don't pass on a good deal if one pops up.
I've had 3 919's GREAT bikes... I'd never trade my RC for one though, that wishy washy frame that's what made me ditch the 9er's and probably why they never really got popular here in the states even us naked guys want performance, don't give me that de-nutted stuff, BMW finally did one right but I cant afford it right now the s1000r. I even upgraded the front end on one 919 but that frame flex or whatever you'd call it was horrific, like throwing a bowl of Jell-o into a corner. I kinda took the riding position naked bike concept of the 919 and applied it to a RC. Now I've got the best of both worlds (hater blockers on LOL)
Back to the RC's the '00-'03 have a black frame and swing arm the '04 is the Nicky Hayden edition (I'd love to get my hands on a factory clean one of these) it has a brushed looking frame and swinger all of those are red black and silver paint schemes the 05-06 have a black and grey paint scheme black frame and swinger.
Hope this helps, I had a 02 03 and 07 919 I loved the paint on the 03
F$#k resale concern you're not gonna wanna sell it, besides they hold their value well not like the poor 9'ers you can get those CHEAP these days. And welcome!