I used the color bars off of my xl2 to callibrate my JVC production monitor. When I bring up the ntsc color bars via Final Cut Pro, there is a drastic differance between the two! the ones from the XL2 seem to be right on as how I callibrated the monitor. Final Cut's are way off, I can see all of the 3.5, 7.5 & 11.5 bars, drastically. So, now I'm concerned as to which color bars I really should have my monitor callibrated to....

Any suggestions on this subject?

When you refer to the Final Cut Color bars do you mean bars generated by Final Cut on your monitor or the bar footage from the XL2 on your monitor displayed by Final Cut? (if that's not exactly clear, in the latter case I mean XL2 color bars imported to FCP and displayed to the monitor).

When I bring up the ntsc color bars via Final Cut Pro
sounds like he means the FCP generated bars

not sure why they are so different but my suggestion: just go with what looks right to you.

yes Mark's right, I was referring to the bars generated from Final Cut compared to the bars generated from the XL2 as I view one or the other onto my production monitor.
And, I guess the bottom line would be as you state Mark to go with what looks good to the eye.

Take 2 seconds of XL2 bars and put them on the timeline next to 2 seconds of FCP bars. Open up your video scopes and look at both, they will tell you everything you need to know. If you don't know what to look for tell us what you see and someone can help. My guess is that the setup level is off on one or the other. Good Luck.