Ralif Redhammer
Legend
In my experience, GWM generally works like this:
Regular attack that hits: “Oh look, I rolled an 18! Next one I’m totally going to use GWM.”
GWM attack: me, rolling with advantage: “Oh look, I rolled a 5 and a 7."
With no calculations, I feel like unless you're playing a Variant Human, the ASI is more valuable than the GWM feat. That being said, when you pull off a GWM hit, it is pretty darn awesome. And that bonus attack, while situational, is still a free bonus attack. It's fun to take down an enemy, then another, just like that.
Regular attack that hits: “Oh look, I rolled an 18! Next one I’m totally going to use GWM.”
GWM attack: me, rolling with advantage: “Oh look, I rolled a 5 and a 7."
With no calculations, I feel like unless you're playing a Variant Human, the ASI is more valuable than the GWM feat. That being said, when you pull off a GWM hit, it is pretty darn awesome. And that bonus attack, while situational, is still a free bonus attack. It's fun to take down an enemy, then another, just like that.