Ya know...I get that "marketing gimmick" line also. And being the "open-minded always willing to try something new diver" that I am...snicker...when I was on a trip last month my buddy and I traded fins for a dive. She wore my Apollo Bio-fins and I wore her Tusa blade-style fins ( I realize that for arguments sake I should be able to tell you the exact model...but all I can tell you is that they were silver/black and quite cool looking. What can I say..chick divers...ANYWAY...)Jarrett:They served me well in Cozumel. I was able to zip around the reefs fairly well. In mild currents, I could get where I needed to go quickly and being a little shorter than my Tusa's I think it helped me keep from kicking people when things got crowded occasionally. I also had plenty of opportunity to try the helicopter kicks with them and that also worked, not as easily as with a blade, but it worked well enough.
The only time I questioned them was on the night dive. Our DM missed the reef and we had to swim against a moderate current for a few minutes. At that point I got a bit fatigued. The DM in her blade fins didn't seem to have any issue, but then again she is like 1/3 my size, in much better shape and dives there daily.
It bears noting that all the DMs and instructors I talked to in Cozumel did not wear split fins and felt they were not the fin to use for drift diving. The more seasoned instructor felt like they were just a marketing gimic.
She surfaced from the dive saying, "I LOVE your fins! They are awesome. I'm buying a pair!!!" And I surfaced from the dive saying, "GIMME back my Bio-fins!!!"
I just can't give them up. I've tried Deep Outdoors tech/wreck style short fins, and I've tried blade-style fins. I know that with my Bio-fins...I can dive day after day, and never feel leg fatigue, can get where I need to go on a dive. I just love 'em. If it's a marketing gimmick...I'm tricked because I really can't give them up!