Great service, be prepared to spend time trying understand the results.
I have a funny shaped head apparently, and my last experience finding a helmet that fit cost me a lot of time and money. So I was THRILLED this service existed.
I suggest taking all of the measurements 3 times because the numbers can be variable.
Based on the results I had very few models to choose from, which confirmed my funny shaped head theory. I would up buying a helmet much larger than I have before, and just swapped out the cheek pads and I have a helmet that fits without an immediate headache. I was able to check the list of the discontinued helmets and was pleased to find that my old helmet was on there as a good fit. So that confirms the service works.
My wife was due for a new helmet as well, and she got the helmet she wanted with no problems.
I took off a star because interpreting the results is not easy. I am used to working with large datasets and having to constantly rate one attribute based on the values of attributes. I still found this confusing! Having the shape of the helmet in green doesn't mean it will fit, because you have to consider 2 other parameters as well.
Nevertheless, the other info they provide is essential. I can't afford the the $500+ helmets so it was easy to rule those out, and I was only looking for a full face with an internal sun visor.