We currently use a 19 foot Boston Whaler Outrage. Also have and have used extensively a 14 foot Novurania Cancuro inflatable and occasionally when I can get it to water an OK Scupper Pro TW kayak.
The BW is easy to trailer, seaworthy when it needs to be, reasonably fast when it needs to be and dives my wife and I and we would rarely invite anyone to go with us anyways. We have Roll Control for holding the tanks, Humminbird Sidescanning sonar and two GPS units for locating dive sites, 300 feet of anchor rode and the usualy first aid kits, flares and safety equipment and a PLB along with a VHF with GPS output (DSC type).
The boating industry does not make very many dive specific boats, BW does or has at various times. Seems to be an under tapped market if you ask me.
We have found that boats in the 18 to 22 foot range, center console type (or probably the walk around cuddy cabin as well) are easiest to deal with and sufficiently capable to get to dive locations and economical to operate. Once you grow to twins, 24-30 foot range the operating costs, tow vehicles, storage etc become too much for many. Boats, all boats, are expensive to own only exceeded by aircraft in being a continuing money drain and maybe motor homes.
I will tell you one thing, in the center console market the metal T top is the status symbol and everybody wants one, for diving and staying out of the sun and for those of us who are fair and blue eyed and burn, a bimini top is much more practical. In smaller boats I also think that a bimini is more seaworthy as it's windage can be removed in a storm by stowing it.
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