I'm not sure you need a provisional licence for so long, the courses tend to adjust accoding to your experience.
For someone of my limited experience in cars I think it would recommend six or seven days.
It's a hard decision really, because I am a sensible chap (as well as a quick learner) and don't envisage having problems with the basic things. The only unknowns are things like motorway driving and these aren't covered (yet) in driving lessons. I don't claim to know everything about driving as I don't, but I am confident it'd be OK if I approach it sensibly and you can only learn properly through proper experience after all.
But if the main opinion here is that lessons would be better I will probably go that way. May as well do what is most recommended.