It's basically the same thing as the previous 940, except now they don't use the IAS designation for the shock valving technology. IAS was a patented invention of Ricor if I remember correctly. Now Progressive uses different nomenclature for what sounds pretty much like the same thing as the IAS.
Anyhow, if you want impressions ask the guys running the 940's. Personally, I have serious doubts about a shock that claims to lower the bike 1" but still maintain the full travel of a 13" shock. What they don't tell you in the ad is that the full travel of approximately 3" is the same as the regular 13" shocks, but the 940/944 instructions tell you to set the sag at 2" versus the normal 1" for the standard shock. So the 940/944 set up per the instructions only has about 1" of travel in compression versus 2" of travel in compression for the regular shocks.
Oh, for those who don't know what I'm talking about, sag is how much the shock compresses from fully extended with just the weight of the bike and rider. Also referred to as spring preload.
Jerry