80% of all the canister filter in the marker are design the same.
if you look at the sunsun and cascade you can see there just the same with the outside of the canister look what so ever.
the other 20% are fx5, odyssea cfs500, fluval, API, fluval g4, and other brand name.
its all about the design inside the canister filter and how each one work.
so which canister is better? i say the fx5 and the odyssea cfs500, why? cause the build inside is build to clean and keep a tank crystal clear. i dont own a cfs500 but seeing pic of the inside of the canister i can tell it was build to clean. I just order one so hope i get it soon.
if i have to pick from a sunsun, cascade, fluval, api, ehiem ill pick a sunsun in a heart beat.
with the price you cant go wrong with the filter if you do one thing and only one thing. HANDLE WITH CARE
the sunsun filter just as good as any of the name i list.
if you want something better and on the low of money i go with the cfs500, if you got money to spend i go with the fx5 or a diy sump. these 3 type of filter i would use in a heart beat.