Wet dry will not remove particles as small as a canister. Thats my opinion.
As for me, I have a wet/dry(used as a sump, everything is in sump/ nothing in tank, plus the flitering of the wet dry), canister, lots of live rock and live sand, fuge with macros and occasionally I hook up the skimmer to pull out the crap.....
Works for me!
Good Luck.