advice about deciding between postdoc offers?


I am currently having a dilemma about deciding between postdoc offers. I have one offer from a lab in the states (I am in the UK), this has been ongoing for a couple of weeks but I still don't have the official offer letter yet as the university requires me to have my PhD awarded before the offer letter. I have my Viva next week, hopefully I will pass but even then I still won't officially have my degree until all corrections are accepted and approved. This could obviously take months and a visa etc would need to be sorted.

Today I received an official offer for a postdoc in the UK to start in the new year. This project is not as appealing to me, I prefer the job in the US but it seems it might be a bad idea to turn down the job in the UK as I obviously can't afford to be unemployed for months, especially when it is not certain when I would be able to start in the USA.

I think I have time to think about it over the weekend but it i'm finding it quite a dilemma to decide what to do. An exciting opportunity in the US versus actual paid job in the UK? Any advice in this situation? Anyone had similar experience of deciding between jobs?