I have been using mine for a few days now and I'm very happy with it. I can tell you that it uses the clearos with no leaks! It also doesn't require any tube at the top, the cup with the silicone cap fits into the top cap of e tank, then you just add a drip tip. I haven't tried it yet but the steel carts have the same connectors and if you remove the tube, they can be used as well with a little o ring added. I'm not sure what the difference is but Arry uses a different type of material for the caps as opposed to the delrin.
Hope this helps.