unfortunatly I wont be that much help to you on several points, I just moved here from Socal. Some of the others may be able to help you there. I'm as in the dark on several issues concerning places and fish. I know that at least in NC were not allowed to spear "reddrum" that fish has several diffrent names depending on who you talk to and where. I'm thinking most of the offshore fish will be african pompano,amber jack, kings, reds,grouper, spanish, etc...
shore diving maybe flounder,sheephead,smaller pompano,cobia,blue fish, thats all I know I'm still trying to figure it all out myself.
I'm very familier with the gun you mentioned very nice gun a couple of guys i know have them and they swear by them, daryl wong makes some beautiful stuff...
Your a better man than I am 3mil in feb I think is going to be a little tough, my best guess is low 50s...
Just a suggestion before you bail Hawaii make sure you grab an extra set of bands for both your guns and wish bones as well it's not easy finding stuff like that here, you will end up having it shipped from somewhere might just save you some aggrivation until you find the right hookup.
I live in Holdan Beach about 35miles south of wilmington and 40 miles from Little river inlet in South Carolina.
So far I've only dove the wrightsville beach area.
Definetly get your buddy squared away, he will love it. pick the best day possible for the first dive 25+vis and no swell, that should get him hooked.