Ride comfort : OK, but not super! pillion rider may hate for ever, you if you take a bad road! Im talking about the very first Hunk.
Maintenance : Service each 3000km , full service with lubrication may cost around 1500.00
Fuel : Out station 40-45 Km per liter if you can ride it softly, no hard acceleration etc, on traffic : dont know.
Hunk engines parts are mostly Japanese, so it will go longer than any other Indian bike, I had one and it did 45000kms without any failure or breakdown till i sold it. But I took care of it very well, it was like brand new when sold after 3 years.
Sprockets n chain lasts about 14000kms, in my opinion, its a good indian bike with a very stupid name
Checkout Yamaha FZ range too. but I dont think any of this comes near to GN or a CM in anyway.