Looked at them and found this a common review for the tire which was my consideration for staying with the Mich GT4. Since I have only ridden Avons on my 1500 and was happy I was really surprised to read some reviews like this one below. It was enough for me to wait to see if I could find any real world experience with the tire since the Mich has always been good.
Review:
Having enjoyed 10 or so miles of dry weather we headed into the heart of the storm. The roads became slippery and unpredictable with pot holes, cow turd and the occasional diesel-spill usually located in the middle of a decreasing-radius blind turn, in other words - typically British conditions. Coming out of corners I would wait until the bike was upright and pop the clutch to see if the rear tyre was making enough grip to pull a wheelie. On almost every occasion the rear tyre lost grip and spun. I tested the Pilot Road 4s a couple of months ago in similar conditions and the Michelins hooked up every time,sending the front wheel airborne on the KTM 660 SMC test bike.
Surprisingly, the only time that the tyre lost grip all day through normal riding was when traveling in a straight line.
It may be hard for Avon to persuade die-hard Michelin and Bridgestone fans to move away from their trusted tyres, but if they manage, there’s good chance those riders won’t be disappointed. They may not be as highly-regarded as other offerings on the market, but the Storms offer grip, performance and longevity, and at a very competitive price too.
http://www.visordown.com/features/products/tested-avon-storm-3d-x-m-tyre-review