***I originally posted this in a different thread, responding to an inquiry for opinions on the Mackie MCU Pro. Another member was kind enough to move my post to better visibility because of my question. Please go down to my question***
I purchased the Mackie MCU Pro a couple weeks ago. (I don't have the additional XT.) I really like that I have tactile contact with the S1 software. All the functions and controls outlined in the Control Link section of the S1 V2.6 Manual Addendum and the S1 Mackie Control Support Manual work as described; transport, shuttle, up/down and zoom controls.
The faders are very smooth and reset nicely when jumping from song to song. Fader controls shift right to left by eight channel banks or one channel at a time. Momentary Solo and Mute functions are (almost) priceless. The LCD track name readouts are only 6 characters long, so alike track names can be confused. This will force me to name my tracks differently.
The MCU allows me to make mixing adjustments without having to look and the screen -AND- I can make multiple adjustments at the same time. I have had no glitches with the MCU Pro.

I do have a question. Has anyone been able to control more than eight plug-in parameters (on one plug-in) with the MCU Pro?
The MCU interfaces with Presonus Control Link allowing the MCU to control plugin parameters by switching the V-Pot assignment from 'Pan' to 'Plug-in'. This is great if the plug-in has eight controls or less.
I contacted Presonus (Ticket #192719) and asked if there is a 'page over' function for additional eight plugin parameter assignments. Presonus responded that at the "present time there is no way to map more than 8 plugins parameters to MCU Pro's eight V-Pots."
I contacted Mackie Technical Support and asked the same question. They responded,"With using the MCU Pro on Studio One you will want the control surface in Mackie Control mode.
If you are using the V-Pots to control a Plug-In and want to see more than the first 8 parameters you can use the left and right arrow buttons next to the scrub wheel to page through the Plug-In settings."
I can't make it work. Can someone test this to help me see what I am missing?
I would love to be able to operate all the parameters on Presonus' Pro EQ.