I have the malamutes and F3.0 currently. Also used the synapse wide for a number of years.
The malamute is a great boot with excellent all-day hold. I've used it in the park and for softboot carving. It is going to take to getting used to but you can adjust the tightness to some degree. Articulation through the ankles is more difficult but I have no problem with my grabs. The 4.0 would be a good choice as well.
You'll notice alot less fatigue when freeriding and better board control at speed.