I ended up purchasing both sizes, the 39L and the 50L. I ended up going with the 39L. In short, for an FJ-09, the 50L is just too big for me. It wouldn't look right. Would be fine on a FJ1300 or other larger bike, but not the FJ-09. When I took the 50L out of the box, it visible looked huge. The overall dimensions of the 39L case are 20" Wide x 15" High x 17" Deep. the Height and depth of the 50L case is about the same, but if I remember correctly (can't find my dimension measurements) the 50L case is about 6" wider. All measurements taken at the widest, highest, and deepest points. I added some pictures to see the visible difference between the two. As can be seen from the first picture, the 50L case looks much bigger. Both cases are very high quality, and the performance of the 39L has been great so far. Hooks up to the mount reliably, and just works great. In my opinion, for an FJ-09 or FZ-09, I would stick with the 39L. Additionally, I ordered both cases, one of them twice (the 39L), and returned two of the three cases I ordered. Motosport was fantastic and easy with the returns. Only cost $6.99 to return each so if you are unsure on what size you want you could order both and pick the one you think would work best. It would only cost an additional $6.99 to get the exact case you want. The local Yamaha Dealer was going to charge me $25 to return one case, so I found this to be a much better option.
