I use the MX-3000 with my Meridian 861/800 system. It works great.

You can access most of the Meridian codes by entering the MX-3000 editor, then select "Pre-Programmed IR Database"

Select Device: DVD, IR Data from: DVD, Brand: Meridian and Model: Your Meridian Device

Some of the functions are missing, but for these I have had good luck with the MX-3000 IR learning function.