My buddy has a JRi on his 2012 and I also have a JRi on my 2010. Both bikes are streetbikes and dragbikes, 1/8 & 1/4. Great shock, very light weight, easy adjustment and for only about $700 you cant beat it. It rides a little more rough on the street than a factory shock because it is stiff and on my 2010, the JRi shock likes my ride height to be fairly low to work the best. Havent had any issues at all with it though. Go for it. The brocks shock is a nice piece but you are getting pretty much the same shock for much cheaper with JRi.
2010 zx10 streetbike/dragbike. 68" wheelbase
STOCK motor, hand clutch, 87 PUMP GAS
5.62 @ 128.53 mph
8.92 @ 153.96 mph