Lipo Question

[Big Lebowski]

Hi everyone. Im new to the boating world i just have a few question to ask about my MG. i have a Octura x642 prop shpr + bal with stock esc and motor can i run 5s with 2 different mahs 1 being 7.4v 25-35c 6000mahs x 7.4 30c 5000mahs?. Also can i run 8000mahs? Can anyone give me a good set up for my mg to hit around 50mph and have good run time, on budget? thanks.

[Visual Perfection]

It isn't a good idea to run two different mah/c rated batteries. If you are going to use a 2s and 3s they need to be same brand, same mah, and same C rating.