Looking for a good deal on a stock rear shock replacement for my '04 919. I'll consider an OEM '07 (I've heard they are slightly better on the '07 than what I have, a stock '04), but would prefer an aftermarket one from Ohlins, WP, Wilburs, etc.
I've got an '07 and I have to say that I was unimpressed with the shock - enough to take the plunge for Ohlins. I'd say that if you can afford it going straight to the best is a good way to go instead of dicking around with wasting money on something that might be a sliver better.
I absolutely love the way my bike feels with the Ohlins on it (though I'm having trouble dialing it in).