Same here.
I'm considering the DGX Frameless mask and it's good to read your comments. Question: DGX strongly advises using toothpaste or a lighter to remove any film prior to use. Here is from their website:
What should I apply to the mask, other than my homemade defog (baby shampoo/water mixture) prior to the first dive?
I used a lighter for my mask.
I recently purchased a Tusa Zensee Pro. It's a much more expensive mask, (about an extra C-note) but I got it for the UV-whatnot filtering lens. It also has an anti-reflective coating to help with light transmission. Used if for the first time DM'ing some OW students at the lake. Easier on the eyes while spending time on the surface. Clarity underwater was good. I suppose when the temperature warms up a scooch more and I'm not wearing a hood I'll compare the two underwater donning and doffing them back and forth to see if the anti-reflective coating actually helps underwater. Granted my eyes are in the over 50 category so they aren't quite as light sensitve as they once were.
The Tusa also comes with a fog resistant film that you apply on your own, not a perfect fit, but covers about 90% of the lens leaving the outside edges. I still used the defog on it, figure when I have a chance to truly play with it by myself I'll try it without and defog and see how it does. I'm not aware of the Tusa having anything on the inside of the lens, as I read the material the coatings were on the external surface. As such, I used the lighter treatment on it without issue.
The fit on the Tusa Zensee is interesting. My normal method of flipping the strap around the front and checking the overall seal, gaps, etc, doesn't apply to it. Where the straps anchor on the side of the skirt it is designed to pull the skirt inwards (my description not Tusa's). Tusa rep had come into the shop and briefed folks on it. When I tried it my way seemed too big, teeter-tottering left to right. But when I flipped the strap over my head as I was supposed to, excellent fit. Even with my mustache it worked well. The skirt was a bit more soft and supple and took a few extra moments to properly set it under the hood when paired with 5mm gloves.
As for the DGX mask: It did finally have a failure. The pin that holds a plastic "barrel bushing" for the retention strap came loose and the barrel bushing disappeared somewhere in the water just as I went to put the mask on. I'm guessing over the many uses over the last couple years (to include letting others use it that may have had it overly tightened) the metal pin in the bit where the strap connects to the mask skirt, worked its way out. I ended up calling DGX to offer a suggestion to prevent it from happening again having some kind of peened head on the pin would keep it from coming out, even if the hole should open up. They listened to what I had to say and ultimately sent me a replacement mask. Now that was completely unexpected as the mask was way past what I would consider a warranty period. Granted my old freezer had a fair number of DGX stickers running down it before it died, and I'm doing my best (to my wife's chagrin) to build another column of DGX stickers on the new freezer. The service I get from DGX just keeps me coming back. When I needed new DUI wrist seals I whipped out my phone and had a new set inbound from DGX ricky-tick.
But it gets better. I got my replacement DGX mask and was diving it not problemo. I found that with the old mask, after slipping the pin back into position, held the strap fine, even without the bushing so I figured I would just use it as a spare. At some point, however, things got moved around and I noticed that I had been making a number of dives on the old mask. Purely by accident and not by design.
TLDR: I still believe that the DGX mask is probably the best value for the money when it comes to masks. I've loaned it to a number of people and it has fit their faces just fine. Low volume, frameless, and one of the best field of views. For those that want UV filtering and don't mind parting with another Benji, check out the Tusa Zensee Pro.