Replying to AT boot advice

Hello guys.
My resort boot is dalbello krypton 2 in size 24.5. I don't use any footbeds.
Also I can't try before buy any boot model, because of the size - no one sells offline 24.5 and even 25.5 shells at least in my country. Buy online is the only option.

I was suggested to buy size 25/25.5, but I afraid that it would be big. I tried my FT in 25.5 and my heel hold was awful. I don't understand how I skied in them. I can't get medium buckle to be tight enough to hold my heel in place. But on other hand I skied 3 years in dalblello kr 2 in 25.5 and they were much better that FT, but on rough snow - I wished for better heel hold (although I started noticing this issue only last season). As I've read around internet AT boots are roomier than alpine. And I afraid if I buy 25.5 size I will be swimming in them.

**This thread was edited on Jan 4th 2021 at 7:20:50am