I will be replacing the Zoom R24 with a rack mount SD Recorder that has 2 RCA Inputs in the back and 2 TS Inputs in the front (you can switch between the 2 for which you want to record from). Now, which would be better to come off the FX2000 to the recorder to get the best sound? XLR --> RCA, TS --> RCA, XLR --> TS, TS --> TS?
Either of the above will work great! This is all based off of preference. I recommend using a standard TS cable for your application. As they are easy to find and may be used for other situations in the future!