My dealer strongly advises against Shell gas as they claim they've had numerous injector clogging issues. The one time I filed with Shell (it was a Chevron that changed to Shell and I just went in blindly, forgetting about the change) my bike did not run as well until that gas was burned off.
I have no idea what Shell is in US (might be different?), but in Canada it's one of very few those don't have any alcohol in a fuel. And is considered the best you can get. Also, I'm not saying that I used Shell exclusively (though, I try to stay with it as much as possible). So, the problem definitely is not in a quality of a gas.
Anyway, I think, I can safely say now that the stalling issue is fixed.
As engine stalling may be different on other Ducatis, I'd like to share the exact problem with mine. After many tries, I found 2 scenarios when stalling occurred the most:
1. 2nd gear, very small, around 2750 RPM (40 km/h or 25 miles/h), steady throttle for 30 sec. Then pull the clutch and release throttle at the same time. Don't allow engine braking! 9 of 10 times RPM drops to almost 0 (tach does not show any bars in Touring mode) and then probably 5 times the bike recovers, but 4 times stalls.
2. 1st gear, clutch pulled. Releasing the clutch (not all the way), giving a little throttle. Then pulling the clutch and closing the throttle. Like when you proceed slowly in heavy traffic. The result is the same - RPM drops to 0 and you have 50/50 chances of bike stalling or recovering.
The solution was RapidBike! I had to add more fuel (enrich) in 0% throttle position column. I have been purposely trying to stall the engine for the last 2 days. Not only it didn't stall once, I also couldn't make it to drop RPM to 0. The worst I saw was 2 bars on the tach!
As another plus, the on/off throttle became much smoother, especially noticeable in second gear/small throttle.
I wonder, why I didn't make these changes before? I guess, I misread RB manual. It says that RB does not adjust first column (0% throttle position), but apparently they reference to adaptation, not manual map setting.
Looks like RapidBike (I have Race model, because I wanted to be able to modify engine braking, but EVO should be fine as well) is a MUST have with this bike, especially if you're looking forward to get rid of CAT.