Best lawn tractor battery

Everything you never wanted to know about batteries and more:
http://www.batteryfaq.org
And you still won't know what the best battery is...
There are definitly internal differences even with same manufacturer. I dealt with this for years on forklift batteries . At a few $K each you need to compare. But we still got bad cells in 'good' batteries. For a lawn tractor battery, most of the warranties are only going to last long enough to cover you if it's junk from day one. I would just make sure it's got the recommended CCA or higher. If it's not a big price gap, go with the 'gold' level. After that - go with Robs answer.