I have 3 helmets I’m trying to choose from for the Vegas T100. It’ll most likely be in the high 70’s low 80’s… maybe warmer, and the bike course has about 4k worth of climbing. I have a Aerohead, Vanquish, and Lazer G1. My main concern is the Aerohead being too hot. I’ve never used the helmet where heat was an issue so I don’t know how good or bad it vents. Vanquish seems to be the middle, and if it ends up being real hot I might use the G1…
More info needed: are you MOP, FOP? What is your objective for the race?
Photos in aero with each helmut would be a help 
MOP towards FOP? My 70.3 times are around 5:15. I’m there to race and do as well as I can. I have no clue on goal times or paces for this race because of the terrain and distance. Not a great photo, but gives an idea… I know my head needs to come down.
Personally I endure heat and sweat to be as aero as possible. Raced in the hottest races in the world with the hottest lids and never had any issue with this.
Your photo looks great. If you are comfy with that Aerohead - go for that
+1 on the Aerohead. I don’t find it to be overly hot (those deep channels in the front really help), but YMMV. You can also ditch the visor and it will still likely outperform the Vanquish (which was optimized for a road bike position and tends to test poorly otherwise).
I’d wear the aero head without the visor. My testing showed the visor only helps at yaw.