For example, I am running a fluval canister and a skimmer on my 55g with no nitrates.
It's entirely up to you. If you have room and the money for a sump then I'd say go for it. The one you linked looked like small models though. Usually you need room for your skimmer, heater and whatever else you wanna put in it.
I've been researching sumps myself but I don't have the room for it underneath for the one I would want. :-(
I would think you can get away with just one of the filters, maybe bail on the hob
one. Unless you can't keep up the maintenance on the canister, they can be nitrate factories if not maintained just so.
Hope that helped some