I am a fan of the G42 as a very lightweight, easy to shoot gun for specific purposes.It handles very much like my full size Glocks. I have used it for occasional use but its primary use for me is for running, cycling. I have done marathons with it as well and can not complain(including a few Ultras). For my usage the weight difference between the G43 and G42 was significant enough to discount the G42. It replaced my LCP which even though was smaller, i found the G42 much easier to shoot under stress in classes including malfunction clearance, reloads etc.
Having said that, I do understand it is .380.