Re: How many "quality" hours should I train outside of class?
IMHO, all you training, inside and outside the dojo, should be quality.
Old sword story: A student ask how long it will take to master the sword? Five years. And if I train everyday? Seven years. And if I train all day everyday? 10 years. Why longer if I train more? Because if your only concern is to mastery everything as fast as possible you will never learn the lesson in today's training.
IMHO, the fastest way to any goal (and beyond) is to enjoy the journey.