I can offer a guess :/ I haven't owned or played any variation of either model so I can only go on what I've read and heard.

The spacing between the two rows seem about equal, both models are fairly uncolored, have great string coverage (blades moreso), and probably sense similar widths of the strings. My guess is there would be a very noticeable difference in performance in the highs, which are far less noticeable as the resonance peak heads towards 2khz and lower due the high inductance of the XL models combined with cable capacitance, etc.

Maybe someone else has better idea?