I have a few of Trevor Burger's EXK1s and LEXKs that are lip flippers. He has recently added thumb studs to these models as an option and I much prefer the thumbstud versions.
As part of a collection, front / lip flippers are nice to have but functionally, on a day to day EDC basis, I'd prefer an opening hole or thumb studs/discs.
Gareth Bull Shamwari Collab! :D I'm digging the front flippers. Makes for a super clean design. Seems like a lot of South African knifemakers are using that opening style lately. Image borrowed from Gareth's Facebook Page.
Current collection: ZDP-189 Delica 4, S110V PM2, St. Nick's 4v Para 3, H1 sheepsfoot Manbug, Kapara, VG-10 Dragonfly, ATS-55 Serrated Delica, ZDP-189 MT04 (not broken yet) + Other non spydercos.