I just flew through IST to TLV (baseball hat) and I can honestly say I felt 100% safe. The airport itself is very much like any other North American airport - shops etc. There are a bunch of burkas walking around -- but most people were dressed very western I did not feel unsafe in the least.
It is worth mentioning that if you can get access to the Turkish lounge, it is worth going in just to experience one of the best lounges in the world.
I know TK is trying hard to promote its routes via IST to TLV and I can honestly say it was a pleasure flying with them. They are flying the 77W on the YYZ-IST route which has WiFi too. ElAl would be wise to upgrade their aging aircrafts flying out of YYZ because even with the layover in IST, my preference would now be to take TK versus ElAl. I love to support ElAl when I can, but I love capitalism more --
-- I can't reward ElAl for treating us like fools with their horrible aircrafts. Sorry.