I've also been looking at both the J and the JTS, primarily for commuting use. My LBS advised that for that purpose the heavier, more robust, frame of the J make it the better choice. The ultralite frame of the JTS is intended for racing and is not going to stand up so well to the long-term commuting abuse e.g. curb hopping etc with loaded panniers. That was their opinion at any rate. Personally I think I'd still be inclined to get the snake. I think it's great value, with excellent components for the price.