Sizing Question
 

I wear vans hi-standard boots in a size 9. I need new bindings and I'm looking at burton cartels and burton triads. Theres a shop in my town that has both, but in different sizes. They have the cartels in a large, and the triads in a medium. I'm kind of leaning towards the triads right now, so my question is, if i get the medium triads this year, and get a larger boot next year, will i still fit into them next year? But if i get the cartels in a large, will my size 9 boots fit in them this year?