I've had a few. They definitely move a lot of water. If I were to buy one again, I would not bother with the versions that have the uv filter. Mine filled with water, making them useless. I would also keep an extra impeller on hand. Finally, I've had the handle that releases the hose from the canister break. So, be gentle with that thing.
I got rid of two sunsun filters and replaced them with one FX6. I'd rather not go back, but if that's what my budget said I had to get, I'd do it.
That sounds negative, but they lasted me a few years, and except for the broken handle and water logged uv lights, they still worked when I sold them.