just do it, you will never look back, but the stock M needs some better shocks if you want to jump big, the HCR does great....
I have no complaints for big jumps/drops on my 08 m1000 once set up right.
Although my back has been bothering me lately
The slow rebound is kind of nice as it sticks when landing... Doesn't seem to bounce much on rebound.
I also agree with m8chris on the trail... The slow rebound works against you if you ride fast and agressive on the trail... The rebound is too slow, and does not react quick enough, so on the 3rd or 4th mogul, the suspension packs, and really causes an impact.
Like chris said, 2 or so miles on the trail I just slow down and deal with it till I hit the powder.
My sno pro eff sled was the bomb for trail and jumping, but I would usually jump another 10-15 feet after landing.
You have to compromise on suspension set up.