Car Rental

Looking through the web regarding car rental for our Portugal trip. Since we are going to fly by BA, we thought we will check out their partner car rental company Hertz, thinking that we can accumulate mileage and also get some good discounts. However, I found out that its still a lot more expensive than our good o' trusty car rental company Budget. We've tried out Budget in various countries (Norway, Iceland, UK, France), and the cars and service that we've received from them are always so satisfactory. Why did we even begin to doubt them? Extra mileage? Cheaper rates? Temptations...temptations..... =)