It seems like when I am trying to expand 5 is better to use than 4 because I win more consistency (or so I think), and then also I have more army's left at the end of the battle that can continue expanding. But I also think attacking with 4 army's would allow me to expand quicker. I was just wonder if anyone had any tips or insight to my question.

It varies depending on the situation. For example, if you're attacking the last territory you need to take a bonus, it's typically better to attack with more so you can be 100% sure you'll get that bonus.

However, if you're 2 or 3 turns away from getting that bonus anyway, then it's better to attack with fewer armies. Save those one or two extra armies for attacking somewhere else.

it also depends on luck settings

4X0.6 = 2.4, so with a luck percentage of what? 20% or less, it could be pointless to send 5 armies, as you would win regardless either way

I have often times used 3 armies to expand to non-essential locations, and 4-5-6+ when i am wanting to guarantee a win, or if i expect an enemy to be on the other side, possibly ready to defend that turn.

Nice thanks for the tips...I'm gonna try using 4 now and see if it makes my expansion faster. I have been using 5 armies for almost all of my attacks to unguarded territories.