After trying and being disappointed by the Omer Zero Cubed mask last year, I picked up a couple of other masks (Mares Star and Sporasub Mystic) that fit fairly well and did not disappoint, but were not the perfect fit I've been looking for in a low volume freediving mask so I didn't feel overly compelled to write a spearview about them. In defense of these masks, they are both low volume masks that are relatively inexpensive so for the money they are great purchases. Of these two, the Sporasub Mystic is the more comfortable of the two thanks to its softer body and skirt composition. So if you're looking for a relative bargain because you don't want to lay out $80-$110 for one of the newer ultra low volume masks, I would highly recommend the Sporasub Mystic.
After the tremendously disappointing experience I had with the Omer Zero Cubed last year, I had gotten a little gun shy about the ULV (Ultra Low Volume) masks but had learned to trust the opinions of those that had forged a path before me. I purchased the Zero Cubed against the recommendations of friends and experts and found their experience to be identically abysmal to mine (Live and Learn - as you hopefully do here). So as more and more ULV masks hit the market (Piranha, Nano, etc) it was with a little trepidation that I considered purchasing yet another mask to try out. But when Cressi announced the Nano and I saw its physical similarities to the Cressi X-Vision (the most comfortable mask I've ever owned) I decided this would be my next foray into the ULV masks (assuming I could afford it).
As I considered purchasing the Nano, this time I asked for and listened to the advice of others I respect and with no one having given a negative impression of this mask, I finally decided to lay out my cash and see what came of it. Spoiler Alert!... I'm glad I did, but I still recommend reading on to understand my experience and the differences between the Nano and the 3 other masks I tried.
I had switched from traditional freediving masks to somewhat lower volume versions about 3 or so years ago when my mask buckle broke and was no longer satisfied with my backup mask as a primary. My first purchase was the Mares Star. This mask has a good field of vision and is somewhat low volume (not compared to the Zero cubed and the Nano but still...). I started using this mask in the Summer of 2011. The mask was a good (not great) fit for my face, but nothing a slight tug on the strap couldn't take care of. That is, until I was in the water for more than a couple of hours. At first, I blamed my discomfort on being in the water too long and then on my mustache, but after giving it the old college try I decided it would make a much better backup and tried to move on. This is when I tried the Zero.
At the store, the Zero felt very good. The seal was great even considering what I think is my narrow face. As I mentioned, I purchased it against the advice of others because I didn't feel the discomfort they claimed with the bridge on their foreheads so I thought I was one of those lucky devils that the Zero fit. Everything was going fine with the Zero until I finally got around to using it with my snorkel in my mouth. I'm not sure why, but the insertion of the snorkel somehow made the mask shift on my face and within minutes, I felt that pain that everyone (or almost everyone) had told me about. I thought I could re-seat the mask on my face and muscle through it, but I found it intolerable and impossible to position so it didnt' hurt. I guess I'm just as Cro-Magnon as everyone else that has trouble with this mask.
I immediately went back and purchased the Mystic which had been highly recommended by other divers as well as reviews in the spearfishing publication "Ultimate Spearfishing" in their comprehensive review of low volume masks (I don't recall the issue). The difference was positive and immediate. The only caveat with the Mystic was that it was just a tad wide for my face so I would have to keep the strap just a hair tighter than normal. Other than that, it is a great mask. But then they announced the Nano...
I so loved the profile of the Nano that I immediately started asking about it (much to the chegrin of my friends at the dive shop). Those few persons that had tried it, had positive things to say, especially in contrast to the Zero. So after considering it for a couple of weeks, I ponied up, shelled out the cash and purchased my Cressi Nano. Here comes the easy part, saying what I love about this mask.
First of all, the fit. The Nano sealed on my face (even dry) so well that I had little concerns about any type of leakage. Then the comfort. The skirt is incredibly soft and therefore incredibly comfortable. I have worn this mask for hours with no comfort issues at all. The slightly different bridge design allows it to hug my face without creating pressure points on my brow so... no Cro-Magnon effect.
The volume is incredibly low. Equalization of the mask requires only minimal air as well as effort which is one of the biggest reasons we use low volume masks, so nothing but plus marks there! Lastly, field of vision. I have not quantified the differences between the field of vision of my last 3 masks and the Nano, but I can tell you that it at least "feels" like the field of vision is wider and less obstructed than (or at least as good as) the other 3 masksI I had tried.
So in conclusion, if asked I would easily say that if you don't mind spending a little extra dinero, the Nano is the front runner among all four and I would recommend it to anyone willing to listen (or read). If money is an issue then I would absolutely recommend the Sporasub Mystic followed closely by the Mares Star. This in spite of the fact that it's my understanding as of this writing that the price of the Zero cubed has been slashed and is now a direct competitor to the other masks mentioned.
As always with any review, your mileage may vary and every face is different so feel free to try things on for yourself but remember to take your snorkel (especially if you're going to try on the Zero)!