Dear Alastair,
If this is just about completion of the PPL, say just 15 hours away from doing the check ride, it makes much more sense to stay in the UK, even with chances of crappy weather.
Plan B would only make sense I you only had say, 8 days of vacation available to do it. If you can afford to do it over week-ends during the entire spring, then under the circumstances you would be crazy to go to the US, or, in your case, "Souf Effricah".