I wore this helmet for a full distance Ironman a few weeks ago. The sun was blazing and it was about 85 outside. The visor was perfect to block the sun rays and I did the whole ride with the front vent closed with no issues at all sweating too bad. Obviously I broke a sweat, but no horror stories of overheating because no ventilation. This helmet is the best looking and most functional helmet on the market for any TT riding. MUST buy if you ask me!!!!

Snug fitting, best in class for vision, and it definitely is Aero and light!
With this helmet, I have no issues seeing ahead of me. I never need to adjust the helmet for vision, it stays in place and does not move.
It is comfortable.
Because it covers your ears it is a loud helmet. Meaning, the sound that gets trapped inside the helmet is heard. On training days, I put in my custom ear plugs (sleeping ones, they are smaller) and it reduces ambient noise. Concentration increases. I also do this when racing motorcycles. In fact nearly al MC racers use ear plugs and that's why I use them on bike training days. Much safer than having music in your ears. I hear everything!
On race day, I go as is (no ear plugs) and there are ZERO issues. I am focused on the race and the noise disappears.
So, I would recommend this helmet to you, but only if you are not competing in my races. I really want to keep the advantage on my side.
Excellent helmet.

Upon first use, I positioned this helmet too far forward on my head, so the tail was sticking up. It generated some measurable time savings around a 20-mile TT course that I regularly do. The next time, I positioned it higher on the head (so the visor is aligned only during TT position, and not when standing up) and the time savings increased. I do think there is a noticeable aero benefit vs. an aero road helmet, even during short TTs. The fit upon the second try was much better, the visibility offered by the visor is excellent. Easy to get the fit dialed in.

Is does take some practice to get it on quickly, due to the tight ear clearance on the S/M (I have a 56.5cm head). Moreover, if you're using for training and using one wireless earbud to listen to music, expect it to be quite difficult to get the earbud in initially (I use Bose Sport); I rode with one earbud for 35 miles, which was fine, but removed it afterwards to relieve ear pressure due to the tight ear flap clearance pressing on the earbud. Probably can work well with wired (less bulky) earbuds.