This is an opportune time to mention that i had been talking out my butt a month or two ago when i said the Active Ankle T2 brace, or for that matter any hinged stirrup brace, would protect against dorsiflex (foot jammed up frontways into the ankle) injuries. They don't, only inversion-type (side to side) injuries.
I broke my left ankle on the slick rock trail in Moab in 2002 and since then I wear ankle supports on both ankles. I use a suport caled ASO they lace up and then have figure eight straps that realy support your ankle from twisting or rolling. And they also prevent dorsiflexion but don't make walking or hiking uncomfortable. I think they are more comfortable than the hinged plastic supports like active ankles and don't make your ankle as wide. You can find them by doing a search for them on Google I found them on a site caled Doc ortho or something like that. I got mine prescribed by my ortopedic surgen and so my insurance paid for half but they were twice as expensive so the price was the same as buying them online.
I just did a quick search and found ASOs for $35.95 each with free shipping at www.asoanklebraces.com this is as cheap as I have seen them and there is more information about them.
I damaged an ankle kayaking, which now gives way occasionally and lets my foot turn under me. I finally settled on a nylon stirrup ankle brace from the local Rite-Aid (sort of a pharmacy/junk store). You get into and out of it with velcro tabs, but it has laces for fine tuning.
One of these days, I'm gonna look like my dad playing senior league softball. More neoprene and nylon bracing than actual clothing.