Don, By all accounts the HJC Symax flip-ups are really good helmets; you've made another wise purchase there.
I stuck with Nolans because I've had them before, so I know that the Large size will fit me like a glove. The Small size is also a perfect fit for my SO.
My [now] old Nolans are open face jobs, but just like you, safety-wise I just don't have confidence in this style anymore, particularly after reading those horror stories (I like my chin just the way it is ... doesn't need modifying by an unfortunate accident!).
Yesterday, on my first ride-out with the new Nolan flip-up - which was just around town by the way - I didn't get above around 45 mph. But around 40 mph the increase in wind-blast noise was very noticeable indeed, much more than my open-face, which never got noticeably noisy until I reached around 65 mph.
The thought of living more "inside" a helmet made me think that I might get a bit claustrophobic, but this is not the case. Vision is not impaired at all, and I actually feel far more secure when the chin guard is down and locked.
Despite the new Nolans "Fog Resistant System", I also feared that the visor might fog-up with my nasal breath. Well it does, but only a little, and then only when wearing it in a stationery position, e.g. stopped at traffic light. The answer is to open the visor about half-an-inch (to the first or second 'click'), and any fogging then disappears immediately. When you pick-up speed again the ventilating system deals with any potential fogging-up. So the visor can be shut again when moving forward.
In summary, the advantage of better protection; the various combinations of visor up -or- down; chin-guard up or locked-down, etceteras, far outweigh the disadvantage of a little extra noise, which I can deal with one way or another.
Executive summary: A real good buy - glad I've got them (also like the cool 'Darth Vader' look!).
Regards
Keith (UK)