Your climate will make a lot of difference for what will produce well for you. I've gardened in a number of different climates and the big beefsteak varieties which did so well for me in the Northeast are not much good, here in Oklahoma. Roma, which has been mentioned in several posts, is widely adapted. Seems wherever it's grown, it does pretty well.
Here in Oklahoma, with our extreme midsummer heat, Roma does well. Heidi, however, is even better than Roma for our climate. It hails from Cameroon, Africa. No matter how hot it gets, this one just keeps cranking out the tomatoes, which is one advantage it has over Roma. Roma is super productive, but after its first flush, it doesn't produce much.