I watch both, but I dramatically prefer boxing...it's honestly about the only thing I watch LIVE.
I usually watch mma on delay so I can get past all the non-fighting bits--- wall 'n' stall and Lay 'n' Pray are not entertaining for me in the least. MMA has more self defense and less prize fighting. Much the same as watching a vintage Wlad Klitschko fight. If your skill is fight avoidance, then I have no desire to watch you perform. Also, there are more cringe inducing "legit" tactics in mma. Foot stomps, covering your opponents mouth with you hand, the oblique kick to your opponents knee, intentional eye pokes galore... just no honour there IMO. Fuck that noise.
Plus, I totally understand wanting to punch a dude in the head, I get that thought three/four times a day. I NEVER have the urge to hug a dude and wrestle him to the dirt. Its the exact opposite of what I want to do when I'm pissed off with some guy. These wrestlefuck dudes seem like they're going to transition into Ultimate Surrender sometimes. If you are on the mat you should be either going for a submission or doing damage. Winning a round by maintaining top position should NOT be a thing. There's a reason that wrestling tourneys are not commercially viable, and that is that they are boring as fuck.
That said, there are must see fighters in both sports, but the further down the line you get, the less interest I have. I don't need to watch mid tier mma, like ever, but mid tier boxing still gets my attention.