mate, it all deppends on what extent you want to go to.. when i first started spearing I started with a seahornet and its a good gun if you want to stick in the shallows chasing smaller reef fish teaches you to get close to the fish.. they are cheap (paid $120) and effective for the close range stuff, however now that i have gotten into it a bit more i got myself a 1.4 freediver rail gun.. now compared to the old seahornet they arn't in the same league but you pay for the difference (paid $340).. with the rail guns you eliminate probable 95% of the horizontal movement in the gun if set up right.. and you can put a lot more power into them and maintaining accuracy at a longer distance...
Nidrac.