2.5 sizes is pretty average for skate size down from sneaker size, I'm a 10 and wear 7.5 but could fit a 7 in some models.
As for the brand loyalty... back in the day Bauer was always the standard cut and CCM's ran wider, so I was always a Bauer person, but I think once the Vapor came out they started having more cuts and then today each brand has all these different fit profiles so it's anyone's guess lol, I switched to CCM a few years back and found they work better for me, also I love their XS holder. Glad you found something you liked and worked best for you.