OK, finally getting around to reporting back.
Did 10 of 11 possible dives at the FG East and West and Stetson banks, including 1 night dive, with the HO mask. (The mask had nothing to do with sitting out the one dive - that was sheer exhaustion since I'd never done more than 3 dives / day before.) I'd have to say its a keeper, but with a few caveats. Dives were all in the high 70 foot to 98 foot sea water range, in water running about 80 degrees at depth and 83-84 at surface (F). Visibility, clarity, field of view, etc were all truly fabulous.
I had no real problem with the mask skirt fit on my face, leakage, etc. One day I even forgot I would be diving soon and put sunscreen on my face to include nose and around eyes, etc. and I didn't have issues with either seal or with leakage/stinging. While I thought the nose pocket was a tad small and hard to 'get to' with fingers around the bulk of the lenses to clear on my first dive with it prior to this trip, on these days I didn't find that to be the case at all. The mask was easy to secure with a hand during the 5-6' giant stride entries off the Fling.
The very first dive I did find mask squeeze to be a bit surprising, as compared to my older low volume mask, until I got the hang of essentially exhaling through my nose almost the entire descent to assist. This of course means I was bubbling air out around the seal a lot and even fogging a bit, but a swish with a little water as I reached my level-off depth took care of that - plus I got back on the boat with some nice 'flags' running from my nostrils as I de-masked <ewwww> - but after that first deeper dive I was much better at meshing the tasks of ear clearing and mask 'inflation' while maintaining a rapid descent to depth.
I did find that after so many dives in a short period of time, with the mask often left 'hanging' on my gear lens-down so that the interior didn't really get a chance to dry entirely, that the anti-fog coating started to work a bit less well later on. But a good rinse with fresh water and spit clean (careful not to use fingernails when smearing around!) did the trick. I never even tried defog on it.
I didn't have a problem with the purge valves leaking (I had 'oiled' them lightly with o-ring silicone at the start of the trip). I will say that I'm not 100% sold on the nylon strap with neoprene patch though - the 'buckles that affix the strap seem to kind of interfere with my snorkel shipping out of the way when I'm not using it. I might just switch back to the plain jane clear silicone strap from my old mask. But that's a minor point and not really significantly related to the mask's performance itself.
The one thing I can say is - the mask will, of course, being polycarbonate - scratch. I managed to take a scratch on the lens on this, my first 'long' dive trip with it, so was kind of pissed at myself. I learned after that (3rd dive or so) that even the 'carpeted' benches of the Fling can have debris on them, so to pull the 'sleep mask' protector over the face of the lens when racking my gear and heading off to sleep and/or eat for the surface interval.
One neat thing about it - some people complain about the fact that with the interior of the lenses being 'domes' if you're face-down in a prone swimming position, any water in the mask settles to the bottom of that. I rarely swim looking 'straight down' so didn't find that to be a problem, but I did find if I did that *intentionally* and held my wrist up to look at my watch 'thru' the little circle of water, it had a magnifying glass effect. Kind of a near accidental bifungle function for us aging types.
Anyway, I think I'll keep it. Volume took a dive or two to get used to but became second nature quickly, and the viz is certainly awesome underwater (reminder - I'm a "naked eye" match for the mask's optics underwater). Even above water, with no vision correction, the mask's sheer size actually was a bit less disorienting to me while climbing up the ship ladder to the dive deck than my old corrective lens could be. Perhaps this is because I don't "mind" seeing blurrily (when I get up to use the bathroom in the middle of the night without glasses, for example) but with the older low-vol corrective mask I had my peripheral vision blocked and the fact that it corrected for spherical only and not my one eye's astigmatism meant the correction was off just 'enough' that I still felt like I had to swivel my head around a lot to watch each foot placement, etc. The more open feeling of the HO mask allowed for me to just emerge more naturally even though I couldn't see crisply.
I never even tried that shippable 'predator' lens thingy, or the monocle. I did keep my old corrective mask in a BC pocket as a backup the entire trip, but never used it. (Only after the fact realized I'd not be able to get the HO with the snorkel attached back into the pocket if I did make a switch!!
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