Not to burst your tomato bubble or anything, but we've had many, many, many, threads here in the Garden, trying to determine what is the "BEST" tasting tomato... And, what we've all come to realize is that, like beauty, "taste is in the mouth of the taster!" Every single person here has their own personal preference!
My suggestion would be to find a local supplier/server of heirloom tomatoes, maybe at one of your local restaurants, or a local farmer's market, and stage yourself a good old-fashioned taste test, to determine which direction your taste buds lead you. Then, you can start looking for the seeds you like. We have benefit of the SE TomatoFest held nearby annually for just such samplings of different varieties. There must be 60-75 different tomatoes available to sample!
However, you can make some determinations of what you like by reading through the seed catalog descriptions, and paying attention to how the growers here describe the tastes. That's how I determined which ones I like best. I had never grown tomatoes, so I read the descriptions. I discovered I lean more toward "sweet" than "tangy" tomatoes, and don't like runny ones. I like meaty, thick slicers that work like a piece of juicy watermelon in your mouth. Holds the juice until you bite into it!
With those factors in mind, I started reading, and was led to most of the "black" heirloom types. Since then, through trial and error, my short list of all-time favorites includes (in this order): Momotoro (Japanese hybrid), Pruden's Purple, Black Krim, Cherokee Purple, and Eva Purple Ball.
I try a couple of new varieties each season, and have yet to bite into a Kellogg's Breakfast or a Black Cherry (which I hear is fabulous!), but, I'll get there.
Also, one variety will taste very differently when "pretty ripe", "ripe" and "very ripe".
To me, Sungold tastes even better (more tart or acid) when not-quite-ripe. They have so MUCH sweetness that they can use the extra "tang" from being a few days short of "fully ripe".
And also, the taste of any variety can change depending on weather. Something could taste bland one year and exciting the next.
And at least some varieties will get sulky and lose all their sweetness and flavor with just 1-2 nights colder than they like. I had some pretty good Stupice that I wanted to show off. So I stopped picking them to be sure I had a few ready for my friend's visit.
Then I didn't notice two cool nights in a row (50? 45?) Then she arrived and I gave her the ripe Stupice. She spit them out: "You think that tastes GOOD?!?" True enough, they were like old oatmeal with overtones of cardboard. The Sungold were still sweet and tasty. So Stupice came up early that year and kept forming fruit despite cool nights, but the flavor went south before the summer was nearly over.
I'm looking forward to the Black Cherry as well Linda. Everything I have read about them says they are the bees knees of cherry tomatoes. If all goes well I may be able to ship some for you to try if you want. About 20 2 foot plants in my basement but ol mother nature is being a real pain in my behind this year. Thought the worse was over planted out my broccoli and wouldn't you know dropped to 20 degrees and I'll be lucky if 2 plants come back. Probably more my fault than hers though.