I purchased the helmet a little over a week ago and only have a handful of rides under it. So far it has been brilliant. The fit is great if you have a Bell shaped head (more narrow than round). The ventilation is superb, and I really love the padding that is designed to deflect your sweat from dripping into your eyes, it has really been working well during the few hot temperature rides. One thing that I will point out is the strap length. A tad too long. I ended up trimming a bit of the excess to prevent it from flapping around in the wind. Overall a fantastic lid!
I wanted a MIPS helmet, and researched several before choosing the Z20. It was not the cheapest, but I knew Bell to be a quality product. And it came in blue to match the accents on my bike. I was quite happy with the fit of this helmet and the adjustments possible make this the most comfortable helmet Ive ever worn. Ive not worn it through the summer heat, so cant comment on ventilation, but so far Im a big fan. I hope I never have to test its MIPS capabilities, but I feel more confident knowing that is part of the design of this helmet.
This is a good looking, non-aero helmet. It seems very well constructed and nicely finished. A bit heavier of a helmet than what I am used too, but also my first with MIPS. Ventilation is good. On my first couple of rides with this helmet I was over-tightening the adjustment wheel thinking it was secured down well enough. This was leading to hot-spots and headaches. Finally figured out that it doesn't need to be as tight as other helmets I'm used to and will still be securely fastened.
I use it primarily on training rides when weight and aero qualities aren't important. When racing I opt for a lighter and more aero lid.