I was actually curious about this precise match up and here are crops of an XR-E vs. an XM-L light (top is LumaPower XR-E w/Turbo Force Kit and bottom is T40CS XM-L) out to 565ft. (172m) at the last column:
To be fair, I think there is something wrong w/the XR-E pill as I only got around 20K lux at 1m (vs. 40K+ for T40CS). Some guy on another thread got 50K+ for the XR-E in this setup.
Full thread here for those interested.