This document attached below should help out a bit, it contains 15+ dragon fruit cultivar descriptions. Rather than top 3, which is limited by personal opinions & taste preferences, here's a thorough sheet with added culture and fertility characteristics. I have enjoyed many and they are all excellent, and we can't fail to remember how nutritive they all are. Happy fruiting...
See the paper it lists a yellow
Selenicereus megalanthus & a yellow
Hylocereus.
Hope this document helps, enjoy.