Yeah works well Fred, I used one for a long time but went back to atomisers purely because I don't have a lot of time on my hands to be cleaning extra equipment than needs be. It will reduce the out flow of your filter slightly as the hose connectors are slightly narrower than the inside diameter of the hoses. It doesn't take much to do that a couple of mm wil slow flow down but that's an inherent issue with all these type of reactors.
One word of caution, the plastic nipple that the co2 hose connects to on the body is very fragile and easily broken which renders the reactor useless. If you get one I use soft co2 proof pipe so its easier to take off when cleaning and if I was you I would put a non return valve a 100mm or so from the co2 inlet and when you disconnect the reactor for cleaning disconnect from the non return valve rather than the nipple on the body so if something does break its not the reactor. Once the pipe is on the nipple try and leave alone. Also, I used to put a smidgeon of petroleum jelly on the thread of the main body to cap to make it easier to take apart later. When it's been running in the tank for a while it can be hard to unscrew these two components as there's nothing much to get a grip on.