There aren't really any decent sight pics out there, so here's a few of my Dawsons. I like 'em even more than my Sevigny sights I ran on my Glock 34.
Rear is a Dawson fixed with a .140 wide notch.
Front is a Dawson fiber front with .100" width, and a .210" height so that my soft competition loads hit point-of-aim at distance. (Shooting factory ammo, or a short-slide, use the .190" front)
The M&P is quite possibly the easiest gun to DIY a wicked trigger on. And the PRO trigger still has a 'catch' during the pull where the trigger bar cams the firing pin plunger, because it wasn't rounded off. So I would have fixed the trigger anyway.
I don't like the Pro's sights. Not enough daylight in the notch.
Those are the only things you get on the PRO, and not the 9L. Why pay more?