I've had Both 650 and 1000 Vstrom. Both are great bikes. The 650 is the better engine although it's down on power compared to the 1000 it's much smoother and free revving. Much better on fuel. If I was road riding only I would get another 650. It's so easy to use and stone cold reliable. 70mpg (uk) is possible. However the AT is miles better than the 1000 if you are going to do anything other than a gravel path. The AT looks better too. It's also narrower than the Vstrom and general easier to move around. AT is better at filtering due to the width. AT feels a lot lighter although I suspect the weight is similar.