Hi Lads,
As Mike has already highlighted - Cabair EU is more expensive but less hassle however due to the current position of the market I think you need to save every penny as in the end you might need to T/R yourself (Easy jet etc...) and what a shameful thing to waste 10,000 Pounds in Spain just because you like the scenery ;-)
The America/Spain portion does not dominate the course therefore I think you can live a month or two in the US.
Just my 2 Quids,