I bought a ProTec Ace helmet a few years ago. They were closing out the purple metalic and only had the Small/Medium left. Being a big guy I figured if it didn't fit me then I had a helmet for my girlfriend. Without the additional fitting foam it fit my head like a glove. The liner foam is very soft and all day comfortable (it makes the liner of the other helmets I've used feel like Balsa wood).
Being painted the surface scratches somewhat easily. I have a habit of hitting strainers and even of hitting my head on the bottom while doing a "fish survey" - and I figure every scratch is a reminder that it has done it's job. I've never had the helmet come loose or even become uncomfortable (get one that fits without adding the stiffer fitting foam pieces). It doesn't grab going over falls or even when you're swimming in a current.
I highly recommend it. I use a soft Salamander visor velcro'ed to it. This helmet is very durable and very comfortable. There is no other helmet that I would recommend. The comfort factor is very important - because you need to have it on for it to do any good...
