Sump configuration

Kelley's lists a sump in their catalog & website, with part of the description stating a 'variety of configurations are available'. Any advice on what to look for in a config. since they will pretty much custom build what you ask for? Like what kind of dimension for baffles, etc. do you guys suggest or just ask them for 'something' basic that is popular? We've never had one before and have only seen one but really don't recall anything special or specific about it. Thanks