As I write this, a youngster in looked like an army backpack just jogged by the window. Looks like he's practicing for one of the military tests.
I own a lot of fins, upwards of 10 pairs. I am a big believer in practicing with the equipment you are going to train with in the situation. The guys I see trying to get into pararescue training up here all use jetfins or rocket fins. That said, I am not sure there is that great of a physiological difference between those fins and the Apeks you have, as they are of a similar design but different materials if memory serves. Except for the holes in the blade and footpocket, they look very much like US Diver Rocket Fins, not surprising since USD owned Apexs. Good luck with your training, there is a kid your age who I have seen swimming three nights a week for the last year to get ready for his. I heard that his tendency to break into the sidestroke during warmups was driving the swim team coach nuts.
One source of rocket and jet fins that I recommend to the pj practicers is to check the local second hand sports stores like Play it Again sports. I sometimes see serviceable jets or rockets in there at $25.