I am in search of a tripod. While doing a bit of research myself, I came to know that there are two broad variants of leg locks, viz. flip and twist lock. In many forums, I find people expressing conflicting views preferring each one over the other. This seems to confuse me even more while not being aware of what each type of lock operates. What are the prime considerations in choosing a particular lock system?
For most people it is just a personal preference. Some say the flip locks are more bulky and can get snagged on objects. Some will tell you that one or the other is faster to set up and take down.
I have both types(Manfrotto flip locks and Benro twist locks) and have no preference. I find them equally fast to set up and take down, and have never had a flip lock snag on something.
Both flip(or lever) locks and twist locks are designed with varying levels of quality. Get a well designed tripod and you should be happy either way.
Keep in mind that in addition to modern flip locks, some older tripods have lever locks that twist to lock and unlock.
I used to have a Bogen/Manfrotto 3205 legset (bought about 20 years ago). (Looks like 190 might be the current model?) I had two complaints about the flip locks:
Now, this is definitely anecdotal -- I have since heard from others that theirs was not that tight and didn't have that level of force. I did try loosening the lock screw a bit (to try and remove some of that force and snap) however the lock wasn't securely tight in that position.
I replaced that legset eventually with something that uses twist locks. They make no noise and have never snapped my fingers.
I prefer the twist style when the tripod is new and in good condition. I find it a bit easier to adjust one-handed. However, when the tripod gets older, or it's wet and cold, or it's been exposed to the elements and isn't functioning as smoothly, it can be harder to get a good grip on the twist collars. With the lever style I think it's easier to get a grip on the mechanism and have enough leverage to open and close no matter what the condition of the tripod.
I've never had a tripod that deteriorated to the point that it wouldn't function, but I have had hiking poles with the twist mechanism, all of which deteriorated to the point that they no longer would hold in place with much force placed on the leg. I don't think a tripod holding the weight of an SLR + lens would have this problem, especially if reasonably well looked after.
If you are going to be adjusting the tripod wearing gloves, or you're going to subject it to sand and salt water, then the lever style may be effective longer. Otherwise it's just personal choice.