Hello, I bought the Suunto Smart Heart Belt directly from the Suunto online shop, and it was delivered superfast after only 24h (from Finland to Italy). Oddly, the product is sold with the Medium size belt (70-110 cm) by default, while Small and Large sizes can be bought separately.
I find the Suunto belt very well done with a really small and light sensor, which makes it quite comfortable to wear. It paired in a second with my Race, and yes, the memory function is compatible (thanks again!): to test it, I started an exercise session and left the swatch in my house while I walked to the gym, trained, and went back, as I stopped the exercise on my Race the one hour and half HR data was there! The memory function is simply great, it absolutely worth the price difference.