The Lindgren Pitman Electrlumes have been tested to 2200 feet for 3 months and no leaking! I'm sure they will go deeper but that's the limit on their test chamber.
As for the
light sticks... I'll have an answer for you guys soon as they will be testing the sticks for me.
I personally haven't had a LP stick leak at all the normal depths we fish for Swords.
I'll be back....
-Tek