I just become Level 25 and got a second yellow sun. I don´t see much difference wrt to having just 1. Each sun gets 12h on recharge (after the other one is charged to). So if you play one at 9am and one at 9pm is the same thing that you could do before with just one sun so not much adventage.
I guess the only advantage is if you play the two of them at the same hour, next day you can play 2 at the same time.
@administrators I think each sun should be charged independently so you could play twice at 9am and twice at 9pm (wrt to having just one sun that you could play only once in the morning and once in the evening), if not there is not much advantage really.
Or am I missing something about how they work?