I just repacked the silencer on my 426 with a Moose repack cartridge. I have always neglected buying the repack kit because of the price, but thought I would give it a shot. I absolutely love it. Very sturdy construction and couldn't be any easier to install. There is also no way for the packing to blow out. All the packing is encased in a "carbon weave" wrap that holds everything together. By using the cartridge, I didn't even have to remove the silencer from the bike. Just pulled the end cap off removed what was left of the stock packing and slid the cartridge in. I was in desperate need of a repack, so the cartridge made a huge difference in the sound of the bike. Much deeper and quieter. I am very pleased and am anxious to see how long it lasts. Moose claims months compared to hours for normal packing. I am very pleased and plan on using the cartridges from now on. >>>$22 well spent!