I had been looking for a street boot with high protection, that wasn't a full height race/track boot, and was not finding what I was looking for. I was using karting high-tops for a while because they were comfortable, but I knew that they weren't going to offer the same protection if I needed it.
Finding the SMX-1R was exactly what I needed. The hard part is buying footwear online, which I would prefer to not do. No one has these on the floor to try on anywhere, so I bit the bullet and after reading a LOT of reviews on these, bought one size smaller than I normally wear. I usually wear a UK 44 (9.5 US) so I bought the 43. Really glad I did because these definitely run on the large size. The 43 (US 9) fits very well, thought I would like to have a little more over-ankle adjustment to help fit my skinny ankles better.
The thing that didn't get mentioned at all is the width. I generally would say my foot is thin, but a wear a standard width shoe. Definitely NOT a wide foot, but these boots do feel a bit narrower than most street shoes, like Vans. When they first arrived, my left foot felt tight and actually caused some pain through the arch. I wore them around the house for a few days (while my wife ridiculed me), and even though they are a stiff, plastic-based boot, they did break in with a little bit of time.
After break-in, they are tremendously comfortable for a sport boot, and feel great on the bike. I would buy these again in a heartbeat. For the price, I don't know if there is a better sport high-top on the market.