I've a 2010 SM-T. About 900 miles on it so far.
Fuel mileage has ranged from low-30s to just over 40mpg. If you ride it like an average motorcycle, 40 should be easy. If you ride it like it wants to be ridden...well, "Your mileage may vary."
Took a bit of work to get the suspension right. It was great on good roads, but I haunt the tight backroads of the Santa Cruz Mountains. Really great motorcycle roads, but often corrupted by ruts, holes, heaves, etc. MY previous Multistrada S (Ohlins) was dialed in to the point where I could ignore road damage. My first forays on the KTM were a huge all-over-the-road-literal-pain-in-the-ass problem. It took several hours working with all the adjustments to get it where I'm now happy. Briefly, the biggest improvement came from setting rear sag.
also... I installed the G2 throttle with #400 cam. That pretty much the sensitive throttle issue.