I've been using one of their clutch levers for two years now. Honestly only a small difference as far as it being easier to pull in, but where it really shines is how easy it is to hold it against the bars. My bike is set up for full street duty and it makes it much easier to hold the clutch in at lights and stop signs without any any strain on my finger/s.
I run one on my TE511 and love it. Makes modulating the clutch int he tight stuff WAY easier and better.
So its less off and on? Which I always hate about the KTM clutch.... always thought of switching to a gas gas setup its much better...
Had one. Sold it. I ended up removing the clutch/ignition bypass switch and replaced it with an autoparts store banjo bolt. That made the clutch about as easy to pull as the MME lever.
BTW, on my 511 I'm running Refurbished ASV Levers. Turns out, however, you can get the Trackside Snap Back Levers from Cycle Gear for about $29 when they are on sale. Just get the ones for a KTM Brembo setup. I'm running the Tracksides on my WR250 and I have to say it is a really nice product. Every bit the quality of ASV.