Well if your used to the handling of the ZX 14 I would go with the 1800 it handles closer to what your used to. It all out runs circles around the 1500 in the handling department . In the comfort department the 1500 has a little more room. I think there both good bikes the 1800 is more spunky though with the extra CC's & fuel injection. As far as pulling trailers my 1500 does fine pulling my little trailer.