I have had very good luck with the SkiDoo bag. I have used mine since 03 and after 4 sleds and 22,000 miles of use they still work good. I am a snowmobile patrol officer in the Black hills and we have 3 sleds with the skidoo bags with no problems except for some broken zipper pulls which I replaced with key chain split rings. The bags do need to be sprayed with a water repellent every few months. I currently have the bags mounted on an 09 summit XP 600 146. I mounted the bags with the straps running under the seat which sets the bags lower and farther back than over the seat. It also makes for a much cleaner installation. I also run a rubber strap through a sewn in tube along the bottom of each bag bolting the front side to the tunnel and streching it tight and hooking the back side to far rear window on the running board. This keeps the bags from flopping around which have destroyed previous bags I have had. I have a 50' section of nylon rope under the heaviest loaded bag which acts as a cushion between the bottom of the bag and the running board. The tighter the bag is packed the better the bag will hold up and the stuff inside will last longer. I use plastic garbage bags for filler and cushion, the garbage bags have come in handy during emergency situations.