Purina Indoor Formula

[CalicoLuver]

I was wondering if any of you fed your cats the "Purina Indoor Formula". My crazy neighbor doesn't think I feed my cats just because their skinny so he thinks it necessary to feed them. He feeds them the Purina Indoor Formula and I was wondering if this was okay for my cats to eat since they mostly stay outside.
I feed them Purina Cat Chow(the blue bag)and 9 lives wet food so they live pretty good. They also get basically any table scraps that we have and they want(makes you wonder how they could be so skinny!).
Just wondering. I assume it's okay but I thought it was like feeding a kitten senior cat food.
Thanx!