Later versions of the XL-55Pro.
Cheaper in price, sure, but in weight, too : a fair chunk of the reduction comes from the absence of integrated magnesium headshell. And this has a sizeable advantage : you can use them on any tonearm you want !
The 44L (red body) and 33L (blue body) differ only in specs : the 44L has more extended frequency response, better channel separation and channel balance. Specs-wise, it is quite close to the XL-55.
I have two 44L, both NOS, the first of which makes wonders on my PS-X800 and PS-8750. Don't be misled by the dull sound of the break in period (if you find one new) : the 44L is a gem.
Note #1 :
Load impedance : the 44L and 33L need at least 100 Ohm.
Note #2 :
Not to be mistaken with the older XL-44 (no "L"), XL-44B, XL-33 (no "L") or XL-33S.