I asked basically this same question about 4 months ago. I ended up with a new, leftover 09 Aprilia Sport City 250. It's comfortable 2 up, gets 75 MPG, will run at highway speeds (80+)and I got it for $3744 OTD. The only real issue I have had is that it looses a lot of speed going up hills 2 up. If you live in a hilly or mountainous area, that is something to consider and you may want to consider a 300 or bigger. Other than slowing on hills, any 250 should be fine as long as you are comfortable on it. If at all possible, take one on a test ride with your wife on back. Without a test ride you may end up with something that is annoying or uncomfortable that you didn't consider. Just because someone else found a particular scooter comfortable doesn't mean that you or your wife will.