How to compare FX futures vs. spot quotes (To get a fair price)?

FX Futures, How much above/below spot prices is acceptable?

To place limit orders on futures so one doesn't get burned with a bad fill

I NEVER daytrade FX, I swingtrade or position trade, so little up/down is still acceptable to me.

So, how much is too much?

 

I think you have that backwards. The bid/ask on futures is in between the bid/ask for spot FX.