Different cultivars of sunchokes do have different flavors, but the flavor difference is not that great. Some are "nuttier" than others. Some taste sweeter than others.

Different sunchokes grow differently in different climates. Some are more disease resistant, as well. Some grow well in short growing seasons. Some need longer seasons to grow well.

Most major seed companies sell sunchokes, but most of them don't say what cultivars you will be receiving.

Fedco and Oikos sell named cultivars.

Fuseau is one of the major commercial cultivars that is grown for sale in grocery stores.

If you look up "topinambour", you will probably find much more info and sources.