This may be a bit heretical, but I’m not really a Boa fan. I have Bont Riot+ with single Boa, and besides the fact that they loosen over time, the need to pull the Boa out to release is inconvenient because it takes some force and there’s not a lot to get an easy grip on. Another, more minor gripe is that the protruding Boa knob makes sitting crosslegged on the ground almost impossible, because of the pressure point. I don’t do that often, but at a break stop on long group ride I might, so it would cool if I could.
Honestly, I’d be happy with the old school 3 strap velcro, or better yet, DuoTec would be ideal because unlike Velcro, it doesn’t absorb water or get blown out and frayed. Velcro and the like are light, infinitely and easy adjustment, don’t come loose, don’t break, easy to make aero, easy to clean, and gift of gifts, you can sit crosslegged on the ground!
Finding all-velcro closures ain’t happening in the high-end segment anymore (right now), though, so let me say this: there are dial-adjust alternatives to Boa, and they may be better. I just picked up some Mavic Crossmax Elite shoes which use a different type of dial-and-cord buckle, one which doesn’t come loose and only needs a counterclockwise twist to release instead of a pull. Better than Boa to my tastes.
I think any kind of dial is only useful insofar as you need to make adjustments, and I wouldn’t pay a premium for two since I can fit my shoes comfortably just using the upper adjustment. I certainly wouldn’t pay a premium for a second Boa.
Mavic Crossmax Elite MTB shoe in orange
EDIT: it’s called Mavic ErgoDial:
Mavic ErgoDial