I'll preface my opinion with, I use Jet fins and haven't really like any of the split fins I've used.
That being said, if you weren't using a frog kick often or you didn't want a heavy fin then I would suggest a Mares Avanti Quattro paddle fin.
Any of the fins like the Quattro that have a flexible rubber insert molded into the fin would work well. My wife uses some Poseidon Forza fins that are construsted the same way. They feel the same as the Quattros.
These fins work well for flutter and frog kicks, and are much lighter than the Jet fin.
Another fin I've used and really like is the Dive Rite fin, the new ones are made of a different, improved material over the old version of that fin. The Dive Rite fin was a little better for back kicking than the Mares, but other than that they are comparable.
I've tried split fins. The ones I've used are Scuba Pro twin Jet, these were too floppy to be of much good in terms of thrust.
They improved it slightly with the Twin Jet max. This is a stiffer version with a hard plastic insert, they are better than the Twin Jet, but I didn't get a great sense of feel out of the Twin Jet max, compared to the paddle fins I've used.
I've also used on a few occasions the Atomic split fin. This fin got a lot of hype from split fin fans, but I felt it was weak in terms of feel and thrust compared to other fins. My personal opinion is that the split fins I used were not very good at all in terms of generating a low gear type of thrust that I like. They were not as good at back kicking either.
I've also used an apollo bio fin. Among the split fins I mentioned, this one was probably the best feeling. Probably due to the stiffer rubber that it's made of.
The Twin jet max is better than the twin jet and the apollo, probably due to it being stiffer than the twin jet, and wider and stiffer than the apollo.
I've also used some Force fins on 6 different dives. The person offered to sell then to me for $75. I declined.
They were pretty good for flutter kicks, not really blowing away any other fin at flutter kicking with dive gear on. They were different feeling than everything else I've ever used, but for diving they didn't really put the hook in me.
I never used them for swimming laps in a pool or anything, but based of how the felt to me I'll bet they would outshine many other fins in this application.
If it were just a streamlined swimmer doing laps, they would be pretty smooth.
They sort of force you into a different and smoother type of fin kick. They didn't appeal to me as a dive fin however.
In fairness, it's hard for me to recommend the old school Jet fin. They're heavy and many people just don't like them.
I'd recommend the Dive Rite paddle fin or the Mares Quattro paddle fin.
Among the split fins I've tried, if someone is just dead set on splits then I'd recommend the Apollo Bio fin.
Mitch
That being said, if you weren't using a frog kick often or you didn't want a heavy fin then I would suggest a Mares Avanti Quattro paddle fin.
Any of the fins like the Quattro that have a flexible rubber insert molded into the fin would work well. My wife uses some Poseidon Forza fins that are construsted the same way. They feel the same as the Quattros.
These fins work well for flutter and frog kicks, and are much lighter than the Jet fin.
Another fin I've used and really like is the Dive Rite fin, the new ones are made of a different, improved material over the old version of that fin. The Dive Rite fin was a little better for back kicking than the Mares, but other than that they are comparable.
I've tried split fins. The ones I've used are Scuba Pro twin Jet, these were too floppy to be of much good in terms of thrust.
They improved it slightly with the Twin Jet max. This is a stiffer version with a hard plastic insert, they are better than the Twin Jet, but I didn't get a great sense of feel out of the Twin Jet max, compared to the paddle fins I've used.
I've also used on a few occasions the Atomic split fin. This fin got a lot of hype from split fin fans, but I felt it was weak in terms of feel and thrust compared to other fins. My personal opinion is that the split fins I used were not very good at all in terms of generating a low gear type of thrust that I like. They were not as good at back kicking either.
I've also used an apollo bio fin. Among the split fins I mentioned, this one was probably the best feeling. Probably due to the stiffer rubber that it's made of.
The Twin jet max is better than the twin jet and the apollo, probably due to it being stiffer than the twin jet, and wider and stiffer than the apollo.
I've also used some Force fins on 6 different dives. The person offered to sell then to me for $75. I declined.
They were pretty good for flutter kicks, not really blowing away any other fin at flutter kicking with dive gear on. They were different feeling than everything else I've ever used, but for diving they didn't really put the hook in me.
I never used them for swimming laps in a pool or anything, but based of how the felt to me I'll bet they would outshine many other fins in this application.
If it were just a streamlined swimmer doing laps, they would be pretty smooth.
They sort of force you into a different and smoother type of fin kick. They didn't appeal to me as a dive fin however.
In fairness, it's hard for me to recommend the old school Jet fin. They're heavy and many people just don't like them.
I'd recommend the Dive Rite paddle fin or the Mares Quattro paddle fin.
Among the split fins I've tried, if someone is just dead set on splits then I'd recommend the Apollo Bio fin.
Mitch