Thanks for the replies, guys. Elie, I've seen the Huco (online) but hadn't heard of anyone using one. How long have you been running with it? Bob, how long have you been running your posi-flow? Where have you fitted it and how is it orientated? I've seen it said it should be in and upward direction at 45 degrees away from the tank. My regulator is set to 2psi. IIRC my SpeedPro Series book said it should be bewteen 1.5 - 2.5 psi. But I know some in the Club are also using 3psi. I spoke to Glencoe and they suggested 3 to <3.5psi, 3.5 being the limit for the needle valve. Interesting stuff.