Hi,

As I mentioned in my answer on another forum, the Key West needs minor surgery on the sponsons.
I'd go for the 9,6V Neodym on 12-14 cells, 16 makes the boat very heavy.

In my opinion, if the boat has seen better days, it's wise to re-inforce the hull with glasscloth and epoxy.

Otherwise you may lose the entire boat in a high speed flip.

I have no experience with the 8,4V 700 motor, maby someone else can make that comparison for you.

Regards, Jan.