My Synthe was 4 years old so figured it was due for replacement. I assume the Spherical technology of the Helios provides a greater level of protection than the Synthe (MIPS only). Overall the Helios has a better finish than the Synthe and operation of the RocLoc is definitely smoother and easier. The Helios uses pad strips in the top which I don't think provide quite the ventilation of the plastic "basket" the Synthe uses. My one complaint about both helmets is that the chin strap buckle adjustment tends to creep loose and require tightening every few days.
I only had this helmet for three months. I was hit head-on by a distracted cyclist on a short bridge accessed by a blind sharp curve. Oncoming cyclists had three warning signs about the turn. Nevertheless, the idiot must have not seen the warnings in time and plowed into me. He fell, got up and fled the scene. I broke two wrist bones and got a concussion. I think I hit hard because I didn't have road rash and cracked the helmet. So, I think I would have suffered greater head injury without the helmet. I like the idea of the ball and socket MIPS design instead of a bunch of sticky dots, but I'd like to see more testing about its effectiveness.
Ok this is another great helmet from Giro, but what can I say that will help you. I'm moving from an old Synthe. I ware a size Med. The Spherical fits just a bit bigger for the same size and just a bit rounder. Having an oval head that leaves just a tiny space on the sides. It is a very close fit between the two. If you like the Synthe you will like the Spherical. Weight, the Synthe on my scale 280g the Spherical 274g. Adjustability is excellent as with all high end Giro's. Cooling, on par with the Synthe (tested in 100F/38C deg). Looks are subjective, I got the Red, White and Black and think the Spherical is the best looking high end Giro. Safety, hope to never know. Ride on.
I really liked the protection and ventilation of my Giro Aether but I was never fond of the fit. I was on the largest size and it always felt a tiny bit too small, a different shape than my previous Giro helmets (Foray & Synthe) and it was constantly resting on my sunglasses. The new Helios is a bit lighter in the large size then my Aether and only just a little heavier than my non MIPS Synthe which is reasonable given the enhanced protection. On the ventilation side I haven't noticed much difference between the two but it's not gotten hot enough here to really tell, my guess is the Aether might be slighter better. On the general fit it's way better for me, no more sunglasses issue, a lot more comfortable especially on the 4+ hour rides. It also has the vertical adjustment on the Roc Loc which was missing on the Aether. Probably the only negative is it does not have the little sunglasses rest in the helmet but it still works fine you just need to be a bit more careful about placing them in enough.
I'm a fast recreational rider, 2-2.5K miles a year, typically ride in the A group. Was running an aero helmet, because I'm all about aero (even my water bottles are aero!) But on hot says I suffered way too much and it impacted my performance. This combined with having gone down a couple times last year meant I needed a cooler helmet and one that provided the best protection I could get. Can't train with a brain injury!
The Giro has proved to have much better with ventilation for those KOM efforts. And I feel better going all out when I know that I have the latest in protection.
I had been using a fairly high end helmet for several years and was pleased and surprised with how comfortable this Giro Helios Spherical MIPS Helmet feels. I hope I do not test the protection it provides, but it is clearly constructed differently from other helmets and that construction design does make sense to provide protection.
Years of having what I would consider helmets has now been eclipsed by what is the very best helmet I have worn. Comfortable, adjustable and extremely light weight while still providing utmost protection. A perfect helmet!
After many years of using a Catlike helmet, my wife returned to using Giro and the Giro Helios Spherical MIPS helmet didn't disappoint her as she really likes her new helmet. It is nice and lite. It fits really well. The adjustability is a simple dial in the back, making it easy when it is on her head.
Got the white one, does the job. Hopefully I won't actually get to test out the power of the spherical technology and the MIPS system but it's comfortable, easy to adjust, feels like I'm wearing nothing that's how light it is and I'm comfortable knowing I have a premium protection system on my head.
My previous helmet was a Giro Aether - so comfortable and light. This is a touch heavier and covers more skull. I'm still getting used to it and wonder how long this break-in period will last.