@TheShark1 as you're realizing, the design and stiffness of fins are a trade off. Soft/split/articulated fins don't put as much stress on your knees (and ankles) as stiffer fins when flutter kicking. But soft/split/articulated fins are crap for frog kicking. Yes, it is possible, but it isn't pretty, or efficient. Softer fins are also a poor choice if you need to fight a current. Stiffer and wider fins (e.g. jet fins) are good for frog kicking, really good for fine positioning, but aren't particularly good for flutter kicks. Yes you can flutter kick in them, but it feels really heavy, and if the flutter kick is going to be your primary kick, they aren't a good choice.
How should you deal with the dilemma? Firstly, it appears you have an issue with tired legs and sore knees when flutter kicking with stiffer fins. You're not alone with that one. Secondly, frog kicking is important to you, otherwise you wouldn't have mentioned it. It appears to me, you are actually asking the wrong question - forget fins for the moment, I think you would be better off asking (yourself and/or SB), "what can I do to stop my knees hurting when finning"? My suggestions:
1) Use the frog kick. It could become your primary kick, but at the very least use it as a regular go-to kick to give your knees a rest - frog kicking doesn't put as much stress on the knees and quads. Don't think of it as a tech divers' kick. It's a great kick for all scuba diving. The more you work on it, the more comfortable it will feel. Get the technique right, and it will feel even more comfortable. Fundies, etc. training will help, but so does getting an experienced (frog-kicking) diver to watch you and give you some pointers. There are also lots of videos on the internet. They are especially useful if you can get someone to video you underwater so you can see what you're doing, rather than just what it feels like you're doing.
2) Work on your leg strength and endurance - finning for an hour or so is not natural for most of us. Training will help. It could be swimming (focus on the kick more so than the arms), running, cycling, weight training, or hiking.
Now, getting back to fin choice. I dive with jet fins. They are stiff, wide, and heavy, and I don't think that's going to suit you. For good, light, comfortable fins that you can use in most circumstances, aren't too stiff, aren't too soft, will work for flutter kicking and frog kicking, I quite like Oceanic Vipers. They come in both open heal and full-foot styles. Like all fins, they are a compromise, but a pretty good compromise in my opinion.
How should you deal with the dilemma? Firstly, it appears you have an issue with tired legs and sore knees when flutter kicking with stiffer fins. You're not alone with that one. Secondly, frog kicking is important to you, otherwise you wouldn't have mentioned it. It appears to me, you are actually asking the wrong question - forget fins for the moment, I think you would be better off asking (yourself and/or SB), "what can I do to stop my knees hurting when finning"? My suggestions:
1) Use the frog kick. It could become your primary kick, but at the very least use it as a regular go-to kick to give your knees a rest - frog kicking doesn't put as much stress on the knees and quads. Don't think of it as a tech divers' kick. It's a great kick for all scuba diving. The more you work on it, the more comfortable it will feel. Get the technique right, and it will feel even more comfortable. Fundies, etc. training will help, but so does getting an experienced (frog-kicking) diver to watch you and give you some pointers. There are also lots of videos on the internet. They are especially useful if you can get someone to video you underwater so you can see what you're doing, rather than just what it feels like you're doing.
2) Work on your leg strength and endurance - finning for an hour or so is not natural for most of us. Training will help. It could be swimming (focus on the kick more so than the arms), running, cycling, weight training, or hiking.
Now, getting back to fin choice. I dive with jet fins. They are stiff, wide, and heavy, and I don't think that's going to suit you. For good, light, comfortable fins that you can use in most circumstances, aren't too stiff, aren't too soft, will work for flutter kicking and frog kicking, I quite like Oceanic Vipers. They come in both open heal and full-foot styles. Like all fins, they are a compromise, but a pretty good compromise in my opinion.
