I love Enterprise and Avis overall, but Dollar at MKE has the best cars hands-down. The other vendors have cars that smell like cigarette smoke covered with air freshener.

Enterprise is great because you can return the car anywhere in Wisconsin with a corporate account without a huge dropoff fee, and Dollar only has the MKE location in WI. However, if you are renting and returning in MKE, choose Dollar.

And their Express program is really good.