AT/Randonee bindings

Many skiers have setups such as this mounted w/ the Fritschi Diamir
Freeride (or Diamir III if they can fit within its 3-10 release
setting range). The boot:ski coupling is a little less rigid than
with an alpine downhill binding, but that's noticeable only on very
firm "snow." If you're not into major airtime, durability is fine
(although a backup toe piece is a good idea on long tours). It
doesn't have all the complicated release angles of high-end alpine
downhill bindings, but those technological advances have had no effect
on the ACL injury rate anyway, so a properly adjusted Diamir is
probably just as safe as any alpine downhill binding.
The Naxo is a worthy competitor to the Freeride, but the heel cocking
lever seems to be prone to breaking. See wildsnow.com for further
details -- in general, seems to be a toss-up on the Freeride v. Naxo
debate.