If you do find that you fit into several, some nice features are
- very soft silicone (there are a lot of variations between masks, some are luxuriously soft, others feel nearly plastic in comparison)
- large field of vision combined with low volume, this usually means no bug-eye masks but the field of vision is kind of tear drop-shape and comes down to your cheek on the bottom (think where the extra field really matters and where it will just be extra space to defog and clear)
- consider single-lens if you don't need Rx lenses, field of vision immediately improved
- straps that are easily adjusted on the go BOTH ways (might not be so important feature for everybody but I like it because I am a fudge-finger) with standard size strap slots so replacements will fit easily
- not many extra 'loose' parts that might fall off (ie sturdy)
Forget about purge. Black skirt rocks.
That said some masks I have liked and use, and could have bought if they fit me are Atomic SubFrame, ScubaPro Frameless, SeaVision (can't remember the model but sublimely soft well-sealing silicone just a little smaller field of vision than I liked), Mares Liquidskin. Cressi Matrix and Cressi Big Eyes did not work for me but would fit the criteria except for soft silicone.