The full face mask I tried was too heavy and confining.
Modern conventional snorkels work well, especially if you wear contact lenses or have optical correction built in. A prescription mask doesn't have to be an exact match, just a plus or minus diopter or two or three, because the water density provides its own correction. But don't put sunscreen on your forehead or brow, to avoid it dripping into your eyes.
I have a very complex prescription, so bought a corrective lens insert that attaches to the inside of the regular facemask glass with suction cups. It works great. I did try it once with a full face mask, and even though it did attach, the curvature of the mask shield made seeing through the lenses difficult, and it did not work so well. I ended up sticking with the conventional facemask instead.
A note about the comment upthread about GoPro mounts on masks: I'm seeing snorkels with GoPro mounts on the bottom end of them, so a camera or whatever can be attached below your chin. Would make it work upside down, but any images or videos could be flipped. Kind of a slick idea, although I haven't tried it yet. Costco currently sells a mask and fins set with a snorkel mount like that.
I like the idea of a GoPro, but can't get around the high cost, for how I'd use it. Then I found a GoPro knockoff camera at Home Depot, of all places, selling for about $25. It has its own waterproof housing and several attachment pieces. Seems to work well, for what it is. I got a kit with a variety of mount attachments at Amazon, which includes a floating handheld mount for underwater use. Will be interesting to try it out when we're in Cozumel at the end of May.
Dave
