neither, a sump and protein skimmer would be cheaper in the long run
and i guess it depends on what you plan on having in there
I had a 29 setup as a temporary tank with an aqua clear and had to change out the filter about every 4 days sprayed it off on day 2. This rank also had a lot of live rock from my display. Ran fine for 3 months but around 30 a month in filters
I also looked into a canister and to change out the media would be very costly
So what I'm saying is if this something you plan on running for a while add a sump and skimmer