Which type of sump pump do I need?

Hi. We are restoring/preserving a 1929 house that sits on a mild rise above ravines in the northern suburbs or Chicago. Not a flood plain. The electricity has not gone off for more than a few hours in the 5 yrs we've lived here.

Our architect and contractor agreed that our wet basement needed trenching/drain-tile, and the initial thought was to let gravity carry the water to the city storm sewer on our property. Turns out our basement floor is about 11 inches lower than our driveway, so we need to pump the water to the storm sewer with a sump pump. NOW, here is the question, do I get a simple single pump with a battery backup or do I get a duplex pump set with alternating control panel (and would this choice require two SUmp Pro back up convertor battery sets?).

We are NOT handy people, but we are usually home and take good care of our stuff.
Thanks!

Duplex pumps with an alternating panel should double the life of each pump and provide for a backup in case one fails.
You would still need a separate battery powered backup if power failure is a concern.

How much you need really depends on what the losses will be if the basement floods. In some areas of Chicagoland you must also consider the potential for combined sewer backing up into the house if you do not have a system in place to prevent it.

Thanks for your help.