I have the Mantra, I want the Sliverax a lot, and I also wouldn't mind having the Advocate, Domino, Dice, Positron, Mamba, and Hanan. But, I also just like them as knives to begin with, not necessarily as flippers first. The Mantra, Advocate, and Domino/Dice are all knives that would be just as good IMO without a flipper tab, just based on design. Positron and Hanan would need another opening method, and the Mamba is, in the words of a well-known reviewer "delightfully impractical" and removing the tab wouldn't change that.
Current: Dragonfly 2 ZDP-189, Chaparral 1, Techno 1, Delica 4 HAP-40, Dragonfly 2 HAP-40, Mantra 1, Ladybug Salt Hawkbill, Nirvana CPM, Endura 4 HAP-40, Sage 4, Para Military 2 CPM Cru-Wear, Sage 5, Caly3 HAP40, Sliverax, Lil' Nilakka, Chaparral Raffir Noble, Zulu, Manbug HAP40, Meerkat HAP40, Sage 1/Sage 2/Sage 3 CF, Introvert, Techno 2