Learning AR10 is useless until you become good enough to FC 5+Star songs. Getting better in general is a way better thing to do especially in your case. AR10 compared to AR9 is quite rare and only appears in maps that you can't play atm. Let's say you were magically granted AR10 reading ability it wouldn't do you any good. Even though you could do a HR AR9 4 star song you wouldn't be able to do a 4.5/5 star even without HR. AR10 doesn't fit most maps anyways. All in all as most will suggest you shouldn't learn AR10 until you really have to, which would be at least rank 5K~.