Arj … I tend not to trade currencies anymore and just stick to S&P (and DOW, FTSE, DAX when can be used as a substitute).
This is because the more you do, the more chance of making a loss or getting stuck.
For me it is all about is all about winning and not getting stuck nowadays.
However to answer your question, I think it depends on your view of the USD. The USD remains in downtrend and if they default or close to, then USD will fall further quickly.
For me on GBP/USD, circa 1.6300 is a must hold. Although I do not believe it can, if that goes then it can get to 1.7xx.
SO if you want to play it your stop will need to be circa 1.6300. (wide range of resistance from 1.6270/1.6350)
I hope that helps, but if you got any other questions, please ask away.
Plan your trade, trade your plan!