yeah, 3 mounts is usually the limit for a ski, after that it starts to get fucked. and if you're going from salomon bindings to look bindings, i dont think it'll be too big of a deal, they might have to alter your midpoint a tiny bit either forward or backward, maybe it'll work out to keep the original one though...but yeah, go for it.
Drop cliffs, not bombs
Make turns, not war
if you have had to remount your ski 3 times, the rest of the ski is probably shot anyways. Going to the look binder should not be a problem, because the heel mounts much further to center than the salamander.
You should belive everything you read on the internet, it's all true.