Been to U.S for 4 years, had a green card, now i live in Israel and have 401k

As I have about $90k in my 401k, I'd like to know -
1) Is it worth rolling the 401k to IRA / Roth? any tax risks doing that? why not leaving it as 401k?
2) What would be the taxes and fees for taking out the money before and after the age of 59.5 ?
I'm 40' , not in urgent need for the money but want to know if it's worth waiting 20 years... I saw different answers from which I'm not sure about two issues -
a) If the 10% early withdrawal is aplicable for me or not
b) As I understand that I'd have to pay taxes in Israel (as addtional income), I don't understand what changes at the age of 60' ? the only thing I can think of is that Israeli taxes may be lower if I'm un-employed the specific year I'm taking the money out - no connection to my age...

Please advice,

Dory.