First year lacrosse stick?

Well this is going to be my first year playing lacrosse in high school and I need to know what would be a good stick for midfield. I don't want one of the cheap beginner sticks. We've been practicing for a few months and my coach said I've improved a lot and I should play midfield. I've only missed about 3 practices total out of like 100+ lol. I was maybe thinking of getting the STX Proton Power? Is it even legal in high school? Any suggestions?