Yes, the RS gets good mileage, though it does depend how you ride. I've always stopped to fill up after 300km (180miles?), so until last week I'd never seen the low fuel light come on. Last week I was out in the middle of nowhere when the light came on after 360km, filled up at 380km and still only got 17.3 ltres into the tank
So yes, I agree with you, the RS is a great bike, one that seems underappreciated by many people (including Triumph who dropped it from the range)