Don't know about L. Did you mean UL? The only difference between the W and one without any letter is that the gaps between the f stop clicks are wider, and there are short lines between the longer lines for half stop settings. Although the W lenses might sell for a little more than the non W, they are usually pretty close in price. The UL is completely different animal. It is physically longer, and a lot more expensive than the original 65 and the W. I believe that the UL has a floating element. Personally, I use a 65mm C lens on my RZ because the wide angle Z lenses are so much more expensive than RB lenses.