The Jet Express is the preferred method for getting to Put-in-Bay Ohio because of a few factors. Just as with anything in life, you do pay for what you get (no such thing as a free lunch), but if you are already planning on spending hundreds or thousands on your day or weekend stay, what difference is $10? The difference is:
1- The Jet drops you off right in the middle of downtown so you can start your vacation immediately (there is a restaurant/bar called The Keys literally right off the Jet dock). The Miller, however, drops you off all the way on the back end of the island and you have to either walk for a half hour to get downtown or rent a taxi.
2- The Jet has free parking, as well as paid parking... just like the Miller. However, the Jet parking is secured.
3- The Jet staff helps you on and off the boat with your luggage. At the Miller, you have to go up and down big hills dragging your luggage behind you (rain or shine, 100 degrees or not).
4- The Jet has comfortable climate-controlled cabins for passenger pleasure on the trip over. You won't get rained on or have to sweat in 100 degree heat for the half hour ride or smell car exhaust fumes.
The Jet Express is really the way to go.