I was a bit skeptical at first when I heard it uses the default flight model but the flight model on the Twin Star is something else. I don't have the 310 or the 414 but I've seen on YT they both fly in a this MSFS way. Twitchy, too sensitive, with no inertia. Not the case with the Da42. It's so good I finally stopped flying the Comanche after 7 months. So I'd say it's not just another high quality addon. It's the second aircraft for MSFS, that I know of, which flies in a believable way.
Great news for the flight sim in general I'd say. When the Comanche came out, people realized how a plane should feel in a desktop flight sim. But it was A2A's own, external physics engine that took ages to develop. The Twin Star uses the default flight model but guys at COWS have shown everyone it can be done. The more simmers try such excellent aircraft, the better. More pressure on other devs to up their game too. So when you hear next time that it's just a desktop flight sim, it doesn't cost $30.000.0000 so it can't feel realistic... Point them to the Da42 and the Comanche.