My 7a is struggling to get to the end of the day with only about 4-5 hours of screentime (music, videos, reading articles, 24/7 VPN, 2 user profiles always open). Should I wait it out for the Motorola phones and survive with a portable battery or just pickup the 10a? The 9a looks like a decent option too, but the pricing seems to be about the same as the 10a.