I watched both but when I watched the american version it was all new, so there was more excitement of course.
the Israeli version is very well made, but its twice as long as the american one with over 40 episodes (twice a week) because they wanted to fill more space. The israeli one looks like there was much more intervention by the production to keep it interesting, so it pretty much ruined it half way through and I stopped watching.
also the israeli one has more models and it sometimes looks more like a vacation with beach activities than a survival challenge.
but you can see it and judge for yourself theres full episodes on their website
ערוץ 10 - הישרדות - עמוד ראשי