There are good flip locks and bad ones, there are good twist locks and bad ones.
Basically, cheap tripods have poor locks be they flip or twist, and the high end ones have nicer actions. I have two Benro CF leg sets with twist, they are fine, no complaints, but they are not as nice to use as the twist locks on my Redged monopod. I have a older Bogen battleship Aluminum Tripod and similar monopod with flip locks, they have a allen wrench to adjust them, but are clunky and catch on things. I also have a newer Manfrotto lower end Aluminum Tripod with flip locks, and I like them. I also have a really old Red Head tripod (whatever that is) that I bought in the 1980's with flip locks. They work fine, but are not impressive.
So, my put is that it is a variable, there are excellent examples of each, and a lot more poorly done implementations.