I wont speak to its aero advantage bc that needs to be tested in a wind tunnel on a specific rider. However, my last three triathlons with this helmet have corresponded with some of my top bike performances relative to competitors.
Yes, its a crazy looking thing like something out of "space balls."
The surprising thing to me is how comfortable it is. Well balanced. Ventilation is excellent, even with the vents covered. Visibility is excellent. It comes with two visors - a clear and a dark one. And of course a big case to carry it and both visors in.
I recently purchased a matte black Giro bicycle helmet, and I'm absolutely thrilled with it! The sleek, minimalist design looks sharp and modern, making it a standout on the road. The fit is spot-on, with Giro's adjustable ROC LOC system providing a secure, comfortable feel without any pressure points, even on long rides. It's lightweight yet feels incredibly sturdy, offering peace of mind with its top-notch safety features. The ventilation is fantastic'plenty of airflow to keep me cool during intense rides. The matte finish is not only stylish, but also resists scratches and smudges. Whether you're a casual rider or a serious cyclist, this Giro helmet is a perfect blend of form, function, and safety. Highly recommend!
I use this helmet for non-draft legal sprint triathlons. I like the ability to easily put a visor on or take it off for travel, different lighting conditions, or for cleaning. it only takes a couple of seconds to put a visor on or take it off. I hold the helmet by the sides where the visor meets the helmet when putting it on in transition to insure I don't accidentally knock the visor off. That has worked and I haven't had any problems in races. I've had other helmets where the visors clip in and are much more difficult to manage.
Synthe MIPS II fit is very good for my rounder head. The straps exit in a good location, adjustability is decent -no issue with slipping when riding over rough patches.
The aesthetic of the helmet profile is traditional and has a wider shape from a front-on view. Those with a narrow facial profile might not like the greater mushroom-top look.
The helmet is not the lightest MIPS available, but it doesn't constantly remind my that my 10yr old non-MIPS LG X-lite one was 45gm lighter.