What to expect with your first tail

[Merman Arion]

foil= floppy harder to lift tail, competitor= strong, easier to lift, but very big, bulky., Merfin= great look, but trickier to swim in.

Raven has made mermen tails but the clients havent seemed to have sent her photos or anything yet

Interesting. Thanks for your input, Raina.
For the Merfin, what did you mean by "trickier to swim in" ?