I lived in a city and had a roofdeck with full sun all day. Tomatos grew amazingly well up there, and the flavor of those ripe tomatoes was so amazing that we had them with nearly every meal. It also made buying tomatos from the grocery store totally impossible.
I've noticed that full sun makes a surprisingly big difference, even with the naturally good tasting heirloom varieties (Cherokee purple, Brandywine, etc.).
I wonder what the science there is. You'd think the slower ripening in partial shade (often a week or more slower) would result in a more complex tasting tomato, but perhaps the flavor compounds never reach a critical mass.
