I have a Lund 1240 flat bottom jon boat. I currently use a 6.5hp mudskipper twister mud motor. I'm looking to get into an outboard. I'm having trouble deciding between a 6hp and a 9.9hp Mercury.I really want the 6hp but don't want to get it and wish I went with the bigger one. I like the cost, the size and the weight of the 6hp and the fact that it has an internal fuel tank. My concern with the 9.9 is the COST$$$, and the size. The 6 just seems more manageable. With my current mud motor I max out at 9mph. I'm not sure how fast I will be able to go with the 6hp outboard but if I can gain a couple extra mph I think I would be happy.