They are all good, reliable, engines. Which one is best for you depends on yout wants and needs. The 3.7 Ecoboost is the best seller, and will get awesome mileage, 23-25 hwy, the 3.5 Ecoboost has the most power, and will tow the most. The 5.0 V8 is very strong, and a good option for all around use.
