Giro has put three years research and a whole lot of investment into its latest creation, the Giro Manifest, a helmet that’s packed full of new tech.

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Does a helmet that costs £250 give you better protection than one that’s, say, half the price? Or to put it another way, can you buy safety? Giro argues that you can.

We tend to agree, the development of new safety systems like Koroyd, MIPS, WaveCel, dual density EPS and more has been rampant over the past few years, and there’s growing evidence from independent parties that these slip plane technologies really do work to reduce the effects of an impact.

The Manifest benefits from the latest Giro tech then. It’s made differently to almost every other helmet on the market, using two EPS liners, instead of one, to protect your head. Dubbed Spherical Technology, built in partnership with MIPS, the two liners slide around inside one another, like a ball and socket joint, and create a slip plane to reduce the forces on your brain from oblique impacts. In layman’s terms, the two parts of the helmet slide against each other and slow down the speed of the impact.

Of course we’ve seen this before with MIPS, but the Manifest floats more easily and moves much more smoothly than any MIPS liner helmet we’ve used, potentially increasing how much force is dissipated. It creaks a little less when you’re riding too. The outer liner is made from a denser EPS to better protect you in high speed impacts, while the inner is lighter for slow-speed impacts.

It’s strange then that Giro didn’t see fit to run the outer EPS liner further down the side of the helmet. Instead, that outer liner sits just on top of the helmet and extends down the front and back, omitting the sides almost altogether. Now I’m no crash test dummy, but it seems the side of your head is a likely spot for an oblique impact.

Removing the usual yellow MIPS liner frees up space inside the helmet for more padding, and the Manifest excels here with X-Static cushioning that really gives the helmet a luxurious feeling. It’s designed to be permanently antimicrobial, but after riding in the helmet for two months in hot conditions there is a mild fug coming from it.

Traditional MIPS liners work best when they have maximum contact with your head, so the fewer vents the better. The Manifest, freed from this problem, has an impressive 19 vents, and what’s more they’re seriously big. Giro uses something it calls its AURA reinforcing arch – a strong skeleton running laterally across the top of the lid and allowing for the big vents. The result is a brilliantly well-vented helmet, noticeably breezier than the Troy Lee Designs A1, Troy Lee Designs A2, and the Oakley Drt5.

Holding everything secure on your head is a ratchet dial that’s really easy to use, and a Fidlock magnetic buckle chinstrap – it’s easy to use but I’ve always found them slightly less comfortable against the skin than a traditional – and cheaper – buckle.

The Manifest is designed to work with glasses and goggles, running the former is reasonably comfortable with minimal intrusion from the arms into the sides of your head. Not as brilliantly unnoticeable as the Oakley’s Drt5, but not bad. Take them off and you can stash them on top, with the arms touching special rubber grippers just inside the helmet and effectively stop them falling off. At the back of the helmet is a rubbery pad to grip your goggle strap, unfortunately it’s not a great helmet for goggles because the peak doesn’t go high enough to park them underneath.

For £250 I expected to get a carry case for portage, or at the very least a fabric bag like almost all helmets come with. Not the Giro Manifest. Combine that with the other niggles, and the sky-high price (even compared with other Giro Spherical Technology helmets like the Tyrant), and it’s rapidly losing marks. However, I still love it for its remarkable breathability and venting, high tech protection, and the fact it feels less like you’re wearing a helmet than anything else I’ve tried.