Jeff, I have the Merc 270 with the air floor and a 4hp 2 stroke mercury. Got it for taking dogs for a walk and shuttling people to the beach (i.e. Sore Thumb). She planes with me on it alone. I got the 4hp 2 stroke because I wanted something light to take on and off the dink when on the hook. To be honest, I never deflate it or take the motor off because it is a pain in the ass. Most folks with dinks start out thinking they will deflate, but most never do. The Merc 270 has served us well for quite a few years - it is a good dink. Good luck, it looks like you have 2 good options on this thread... If you can find a 2 stroke I highly recommend it because you do not have to worry about how you lie it down and having the oil run out of it. I got mine new from busters and it was one of their last small 2 strokes they sold.