I've never owned a closed heel mono and I've always sort of shunned them.
But I'm thinking of getting one now for purely recreational diving. The performance difference is there, but it's not big enough to justify the pain of wearing the Flyer I now use
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The flyer is great for a couple of deep dives, but in a session where you may have to swim a little to get to the dive spot and maybe spent an hour or two in the water - it is sheer agony.
So my recommendation for purely recreational purposes would propapbly to go with closed heel. It's comfortable, warm, easy to put on (don't even get me started with the flyer - better have some lube with you), functions reasonably well, is durable, easier to get the right fit (or rather, even if it's not absolutely right, it still won't destroy your will to live).
I view the difference a bit like do you have a smoothskin wetsuit or nylon lining in the outside. I've gone with the nylon so far, simply for comfort reasons. I don't have to worry about climbing rocky shores or be extra careful when I put it on. Simply throw it on and go diving. Sure it has limitations, but I view it as a better compromise than an ultra teary suit...
Anywho, if you're the least bit interested in performace oriented diving, especially pool things and looking forward to honing your technique in those long winter nights...Then I'd look into open heel.
But better yet, if your budget allows, get both! One for pool/training and one for fun diving...
A good fitting Andronov type would probably be the best (is it called semi-closed or something like that). But damned, if you know where to get one a) reliably (you get what you order, not for example 3 sizes smaller and completely wrong stiffness) b)for a reasonable proce c)without 6 months waiting and fluent skills in russian, let me know
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