I have The One boot by Flow and love the fit. The liner has a velcro strap that you can get nice and tight around your calf. Even better, the liner's speed lace is actually attached to the back/inside of the boot, so when you pull it tight it pulls the liner (and your calf) snug against the back of the boot. They use lace-lock eyelets (they're also available with Boas, but I'm old school when it comes to laces) so once you get the liner tightented up, you can lace up tight around your upper calf and they stay that way all day. Rarely do I have to stop to re-lace or tighten them up.