I don't know about the yami setup but thought I would give my opinion on what I do know about the kmod.
I have a 09 twisted m8 153, on low boost 6-7lbs, when turning up hill it was near uncontrollable for my style of riding and eventually it would climb a tree or put me somewhere I wasn't intending on going. It still worked and most around here don't ride as hard or try the stuff I do.
After hearing from Shain, Amber Holt, and some others about he Kmod I figured it was worth a try but only went with the cheaper upgrade with reworked shocks and rear arm, cost $1000 and figured I wouldn't be out completely if I didn't like it. I am rather skeptical about spending money without proof but figured with the references it was worth a try.
I was amazed, everything I had done before and worked my butt off to do was now happening with a lot less effort, and I was pushing harder and farther than ever before even on the first ride. After one day IMO a turbo sled isn't half of what it should be without a KMOD under it. I have since ran on average 10lbs but go anywhere from 6-13lbs of boost and made slight adjustments here and there to the shock pressure and bump stop on the rear arm depending on boost and conditions.
Most everyone has seen "school again" or at least the teaser, thats how I ride. Before the kmod its how I tried to ride but struggled. Its been the best season in my life because I now longer look at things wondering if it can be done, I just take off and figure it out when I get there. The Kmod allows you to sidehill steeper hills with better control, stays on the snow better and all around better ride than what I had.
When going straight up a hill and your not going to make it I can trench it in until it nearly stops the jump to one side and drop into a sidehill and take off again, or just lean back on the boards and pull a little to one side and it does a u-turn that is so effortless it wasn't until after I did it that I realized what took place, so I did it a few more times. I have mine set farely soft and it will wheelie a bit but not to much, even with the skis 4' in the air I still have control and have shot through trees that where so tight I only had about a few inches on each side with the skis in the air and still felt in control. Sidehilled slopes so steep there was no room to hang a leg and had to hang it over the hood with my side rubbing the snow.
Switchbacks are way easier, I can do them around a single tree which makes any line possible. Even when sidehill the steep across humps, bumps or wind lips you can keep going, where as the stock skid would wash out or trench in the kmod land better and returns to the line better. On the stock skid I had tried catching air in a sidehill off a wind lip and then landing a sidehill and was stuck shortly after. I pulled it off a few times but wasn't pretty. I have now done it many times with the kmod, its one of the coolest feeling catching air while hanging a leg then tuck it in while in the air and then back out to land right back in a side hill looking for the next one.
I later went to a 162 and it was pretty much the same but climbed higher and now I'm thinking of going back to the 153 for the challenge. The 153 is a little tighter on the switchbacks and can be thrown around trees quicker, if I need to go higher I will just crank the boost.
Next year with a new sled I will be going with the full package with raptor shocks, the current valving on my shocks is good but I can guess how much better the raptors will be.
As you have read I am 100% sold on this product and the support. This skid works. Thanks KMOD.