That whole solo in 15 hours thing is Bullsh*t, i don't care how long people take, it doesn't really matter, its how they grow as a pilot and the mentality.
I took longer than 15 hours simply because my Medical was delayed due to an argument with the CAA (i don't have asthma BTW) instead of saving my money and staying on the ground i kept working through the syllabus until my med cert was done, i'd pretty much completed most of it by the time the cert came through.
I had a very overcooked Solo.
I'd rather fly with a thorough ''nana'' with better cockpit checks than me.. than a sh*t hot 6 hours to solo top gun type.