FF,
I'm just finishing my first year. With 1 kid, we haven't saved a dime. In fact, we've come close to dipping into our savings a few times. I'm told that that is typical for the first year. I would hope to have a modest savings program next year. Probably no more than 400-500 USD per month.
Having said that, we do balance living and savings. It'd be tough to live here if you didn't open up the purse strings and live a little.
Bottom line is that EK is not a get-rich-quick type of ex-pat job. Over the long haul, I think it will work out, but short term...