On Sat, 12 Jun 2010 09:39:25 -0400, John H
wrote:

What he said.

The only advantage to a West Marine battery is that they cost more. WalMart is
the way to go for a deep cycle, which is what you need.

The very best value in a true deep cycle battery are the 6 volt golf
cart type. You can buy them for reasonable prices at Sam's Club or
your local golf cart dealer, typically for about $75 each. You need
two wired in series for a 12 volt trolling motor. We use 8 of them
wired in series/paralell for the house bank on our trawler and deep
cycle them twice a day when we're living aboard. That is tough usage
for a battery but we usually get 3 or 4 years life from them.