Mostly in the bay. We are going to practice shooting in the bay first then go to reefs
Hi Mark, Which bay, where? How far can you see (in metres) in the water there e.g. are we talking gin clear or pea soup? This will help determine the appropriate length of speargun, which is perhaps the most important detail. If you don't know this, it suggests that perhaps a roller speargun is probably not the most appropriate choice for you, as Kodama already suggested. Speargun length affects power and range. However, the need for power is generally greatly overestimated and other important factors underestimated, or not considered at all, by beginners. For example, ease of loading, balance, accuracy, comfort, appropriateness (e.g. for user, fish size, visibility and conditions), availability of support and spares, warranty.
As somebody already mentioned above, the size of fish you are targeting is an important consideration. For example, I tend to use slim, superlight spearguns these days but they would be inappropriate for large game fish. These are nimble, fast tracking spearguns for the poor visibility and fast moving, modestly sized fish I most often encounter. At the other end of the continuum, heavy duty clips, lines, floppers, etc. and special float rigs are required for big, powerful fish. Horses for courses.
There are some very good American makers, as well as manufacturers and resellers, of spearguns, others can probably advise on that. Darryl Wong (in Hawaii) and Setting Steel are a couple of high end makers that spring to mind, not sure if they make roller spearguns. Mako sell robust, powerful railguns, not sure if they do a roller (Dani?); an American company selling product produced in Taiwan, I believe. I believe Riffe manufacture in California(?).