changed the old milwaukee sm122 ph controller for their new model MC122 ph controller. first impression the quality seems a little better. the size is nice and small. the display is a little bigger, and the knob for set point feels more sturdy and stays right where you set it. I try to keep all my gear as up to date as possible. I will be installing a pinpoint PH controller on another tank so if you want any feed back on a side by side comparrison feel free to ask. I did have a few problems with my old sm122 such as an ocasional chattering sound when it would hit the setpoint and the unit would not turn off, ended up gassing the fish to death on a couple ocassions. spoke with Milwaukee who blamed it on the outlet. Funny thing is if you replace the Milwaukee probe with a pinpoint probe you will never have the issue and it will work fine.Asked Milwaukee about why this works and got no comment!!! funny that now they redesign there ph controller.