I've been using the Radical ST 2's on my inbounds and backcountry skis: 30 days this winter. I've been very happy with them.
No real pre-releases to speak of - even with plenty of ski patrol work with heavy toboggans (with heavier people loaded) down steep runs. And i'm a bigger guy to begin with (210 lbs). Of the few wrecks i've had where they needed to release they did.
On the tour side of things ... 100%. No releases, no problems with ice, no problems with brakes ... super solid.
I'd recommend thes...