Hello 7mm Mauser,
My favorite speargun maker is Riffe.
It is because they are not only well made but, equally as important as high quality is, they are also very quiet.
For any non-spearfishing readers, wary gamefish will "jump the spear", if your gun is noisy to shoot, just the same as nervous game animals on the land will "jump the string" for bow hunters, if they hear the "thwack" from shooting an arrow at them.
Riffe makes everything from very short and handy ones for reef fish and flounder, etc., to very large and powerful "blue water" models, for huge and powerful pelagic species, like tuna and such.
Web site:
speargun.com
These days, people tell me I am 63 years old but, I still spearfish whenever I get the chance (almost entirely only at Hawaii these days).
Due to my age, I no longer try for any species except "reef fish" (goatfish, parrotfish and other similar sized, in-shore species).
However, when I was young, twice I have been dragged through the water by large fish that I had failed to hit correctly (missed the brain or spine).
One was a very large leopard shark (essentially they are a spotted sand shark) on the leeward side of Catalena Island, 26 miles off the coast of Los Angeles California.
The other was a huge black sea bass.
I eventually landed the shark but lost the bass when, my weak and mangled single barb tore back through some flesh / scales and pulled free, as I was braced against some rocks he had taken refuge in.
I was pulling for all I was worth and so was he but, my cheap equipment (flimsy Voit brand, 1965 vintage aluminum single band gun) had not penetrated very far into the bass.
I realize that only being dragged by fish twice in my life is very limited experience, compared to some guys but, those two experiences caused me to seriously think about my spearfishing equipment.
Back in those days, I settled on the tag-line / float system, instead of the reel.
In other words, you attach a line and streamlined float to your "breakaway" toggle-barb.
When a fish is skewered through a non-vital spot (never intentionally, as on truly large fish, you try to brain or spine them), he bolts and the barb pops free of the spear shaft.
Mr. Fish then races about, dragging the float until he runs out of petrol, and Bob's your aunty.
The "fighting reel" on a speargun system always concerned me that a large fish might swiftly encircle me with the line, as I'm furiously trying to reel him in.
Admittedly however, I confess that I have never tried the reel system on any speargun and so, my concern might be nothing more than unfounded nonsense.
Stay safe and cheers,
Velo Dog.