I'm surprised that no-one's added to this thread in 2 1/2 years! I just bought a 2019 V7 III Stone Night Pack, and like all Guzzis it has its quirks. Some I don't notice as I'm used to Guzzi - I love the crankshaft torque effect at idle! Gearbox is surprisingly light and smooth, much better than the '97 Sport1100i I had. As for MPG, I only have about 550 miles, so time will tell, but for the first couple of fillups I'm getting around 53mpg. Interestingly (and annoyingly) the "imperial" setting for the LCD readouts seem to be UK, rather than US. Miles are obviously the same, but US gallons are smaller - the readout is clearly in UK gallons as it claims 65mpg or so, about 20% high. Irritating. Although I agree with Godrfrey in not trusting the ECU's claimed mpg!
The other annoying "quirk" is that the check engine light came on the other day. I called the dealer and arranged for them to read it the next day, but when I started the bike to ride over in the morning, the CEL went out as normal. And hasn't come on again since. Oh well, hopefully it was just a glitch. I had met with a friend who wanted to hear the engine, and we got to chatting, and it probably idled in the warm sun (75F) for 10 - 15min before I rode off and noticed the CEL was on. Perhaps something overheated or vapor got stuck somewhere and it didn't reset until left overnight.
I'd like to add a Dart flyscreen but sadly they don't make them (yet) for the Night Pack with its different headlight. I contacted them, and they said the do plan to make them, once covid is over. I'm also hoping that the 2021 models will have the same headlight arrangement, giving them more incentive!