I have owned both and currently have a 518L. Either choice you make will put you in a boat that is absolutely fantastic. I have owned 2 bass cats. a classic and a IV. Both companies are also fantastic to deal with as well if you want or need something after the purchase. I found that the Cats were defiantly a faster ride and what I felt was more fun to drive but as I got older and not as much into the top speed giving up a a couple mph for a more stable platform while fishing was one of my reasoning for making the current change. The Ranger defiantly shines with the TM down in this class of boats as the cats do with speed. I currently see it as I only have one race and that's at blast off the rest of the day it is about the trolling motor being down and the 518 with a 200 will hit 70 so its not a slug. The customer service from both companies could not be any better. My advice would be to you if the interior lay out in one is not a difference maker and the speed or stability small differences don't matter to you put some consideration into the dealer that you have close to you that will be taking care of you after the purchase, that is the part that made my final choice for me. Post a pic of what you end up buying !