i've had good luck with mine, fittings all stay dry so no leaking.
i think i have a MJ600 or MJ900 on mine. it comes with a ball valve attachment so you can cut back flow depending on what media you are using.
i never have any luck with the phosban making any difference (i've always have non detect on my phosphate readings anyways). and after a couple of weeks of phosban being in the chamber, it seems i get more algae growing in my tank.
i currently have some large pellet carbon in it now, and the ball valve is open all the way so there is some good flow going through it, but the carbon isn't moving creating any dust. this method seems to work better for me than using the phosban. great product considering how cheap it is.
almost makes buying a canister filter not even seem worth it anymore due to the cost.