Great Minds (Franks) think alike
Just got a 30 min ride over the weekend and the shock is firm but not jarring, my old shock is like marshmellow compared to the 08 shock. What I like the most is that now I have more weight on the front of the bike, I put a 110-70-16 which lower the front and a 1/4" longer 08 shock further the bias toward the front and I like how the bike handles now in corners.
I got progressive springs with no spacer (per instructions) and its a little soft so I put a little more fork oil and 1/2" spacer in each fork and its a little bit too stiff so I might take the spacer off and see how it feels with just the fork oil increase. My 87 E2 only got 35mm fork tubes, 88-07 got 36mm and 08's got 37mm.
If you can find a 08 shock then by all means go for it, its really a bolt on installation. If you go touring with your ninja then stock might be better option but if you like canyon carving a firmer rear shock is always the way to go