All of the suspensions offered above are top notch skids.
The Alpha-X and the Timbersled Mountain Tamer-X both have the DSC (Dual Speed Control) on the compression side of the rear-track shock that give you even more adjustment to the skid, With a ton of adjustments available to you....rebound, DSC compression hi/lo, air spring rate, shock position, (transfer and coupling adjustments on the T-sled)... this will be at the top of the list with very few others on the suspension offerings out there. This new shock allows the rider so many different adjustments that will handle anything you can throw at it!
Most mountain riders will not need the "X" model option on the T-sled and can go with the standard float option.
I've spent the last week on the demo Timbersled Mountain Tamer suspension... It just plain works in the mountains. It gets up on top of the snow better than any of the other lightweight suspensions that I've tried so far... and I have tried all of the offerings mentioned above. I'm riding the same sled that you have... I'm buying the Mountain-Tamer.
Hillclimber, It is unfortunate that you have had such bad luck with the your suspension.. I have personally seen the T-sled skid take some serious punishment.
I have watched 3 High Level (Burandt level) riders punish the Timbersled skids for the last week with Turbo and Naturally aspirated Polaris and Cat sled and not one problem. One of them was the original Timbersled edition that was purchased 3 years ago with only the bushing update. .. didn't skip a beat.
Proper installation, setup and maintenance are crucial with this skid and the other Brands as well.
Dan Adams, a factory Polaris sponsored rider gets any skids he wants.. he IS a big hucker and freerider and has not had issues with his Timbersled Suspension.
Chris Burrandt has the Timbersled on his sled and he has just ordered more of them... one of the other skids mentioned above is getting taken off to put in the Timbersled... and again he gets whatever he wants.
There are lots of choices out there.
The Alpha-X for your sled is $2200 plus a fair amount of your parts from your stock skid. (you don't need rails for the 2008)
$2500 for the skid with rails and some parts from your stock skid
Note: This kit will fit '06-'08 IQ/RMK models. This kit will not fit '09 models; Rails are required for '09 models.
The EZ-Ride is about $2500 and is a bolt in deal.
The Timbersled Mt. Tamer is $1600 for your stock rails... $2000 for with new rails... keep your stock skid intact and sell it or keep it so you can put it back on if you sell the sled or loose it to insurance.
What is in your budget/plans makes a big difference in recommendations.
Also, qualify the recommendations that people are making on aftermarket products... ask what engine mods/turbos, tracks, lengths, other add ons (spindles skis etc), type of riding (chutes, mogul basher, tree rider, powder hound), and rider size/weight so that you are evaluating your purchase )from others in a similar situation.. (for example... if you have a 146" Assault... a turbo 163" hillclimber might not have same needs or goals.
Different purposes for riding require different equipment and setups.
For the Can...[muffler] My preference is the SPG Ultra-Q silencers... compact, very lightweight and quiet. I'm not a big fan of stuff that is loud... and with more states slated for sound level checks like Colorado has this year... something to think about.