I was one of the original consumer testers for the F1's. Still have the prototypes for the all black and the yellow tips that came out later. Great fin for OW dives and high current applications in my opinion. I have them in XL in the all black for use with my heavy wet boots and rock boots and the yellow tips in large for thinner boots. They are heavy but I have had mine to Bonaire (first place they were in the water), Monterey, and Puerto Rico. The F1's are designed to be neutral in salt water so they are naturally a tad heavy in fresh. I like the three position options for the spring straps. They are however expensive and I have a rule to never pay more than 125 bucks for fins. Both sets of my F1's cost me a review of them for Hollis to use.
I don't do caves at all. Maybe some day as I have a number of friends who keep telling me to try it. I am a wreck diver and for those I have been using the HOG tech fins for a couple years now. They are not high speed, high current fins. Never were purported to be. They are designed for use in tight quarters and they excel there. I like them better than the F1's, my old Aqualung Blades (the originals- not the junk Blades2), my Aeris Vectors, Rockets, and Jets I was able to try. Jets hurt my feet. Rockets and Super Rockets only fit certain people, and others are too long. No problem maneuvering in a dry suit with the extra drag.
I own at least 6 pairs of scuba fins. Some I have not touched in years but I still see the possibility of using them at some point. I have owned over a dozen. Many were bought and resold. At one time I had 4 sets of blades. Bought cheap on ebay and sold for a profit.
The best thing to do is try the fins in the pool. The shop whose pool I use has over a dozen styles and makes of fins for students to try before they buy. I'll bring in my F1's for them to use since he is a Hollis dealer and my HOG Tech Fins since that is what I sell.
Edge also had an entry level fin that retails for around 50 bucks that is surprisingly good. I have a couple pairs of the Transcend on hand.
Their new entry level one is a bit more but I have been using them in the pool. A little soft for my tastes but the foot pockets are nice and it comes with a rubber bungee style strap that is available in different lengths. Kinda like a spring strap but less expensive.