Split fins tend to buckle under a heavy load when you are kicking hard. This is not a problem for people with minimal leg strength, but it's a PIB for us with an overabundance. I used Jets for a long, long time because when I kick hard, the water moves: not the fin. Last year, I tried a pair of Hollis' Bat Fins (FS1???) and simply loved them. They even hold up under a full load pulling a tired diver in real life. Split fins are fine and are great for the recreational diver. Those who want to be available to help others should be sure that they are appropriate for their kick style while pulling a load. The only way to know is to try it out.