Hi man!
Sorry to hear about the bogging problems!.
I have the same problem with my 1999 SRX, here`s one of my threads:
http://www.totallyamaha.net/forums/showthread.php?t=27126&highlight=bogging
Do a search and you will find several threads about this problem.
For this season I`m getting a Bender Cold air kit, Bender canister and I`m going to make the exhaust deflector larger.
It seems like (from what I`ve read here and there) that the bogging is or can be caused by:
1. The exhaust doesn`t leave the sled due to snow buildup around the exhaust outlet, a deflector must be installed. (bogging from exhaust struggling or see below:
2. Improper sealing between exhaust outlet/chassis so that the exhaust find its way back into the hood, engines doesn`t like co2 with no nutrition
3. Air starvation, the hood vents get blocked by snow, the engine therefor bogs due to rich mixture.
PS, I don`t have a doctor deegree in this so don`t judge me if I`m wrong

.
It`s so frustrating for me to watch my friends with older V-Max`s (V-Max 4, V-Max 600XT and so on) busting through the powder with no problems.
Last year I had to turn around and go home due to powder problem, man that was annoying.
Good luck!