If you decide to pursue kayaking or the surfski, there are two major components you will need to develop. The most important is paddling technique, which is extremely important in your stability, as well as speed and ease of traveling on the water. The second is aerobic and anaerobic conditioning, which will allow greater speeds and still greater distances.
Step one, you need a Wing Paddle. If you don't want to go out and buy one, you can read on and most of this will still apply, but you will never "be, all that you can be" unless you get the wing paddle. The wing paddle is a revolutionary step forward in the way a kayaker can move his boat forward. It actually forces you to use the larger muscle groups you are supposed to use anyway (if you thought a kayaker was an arm paddler, you're in for a shock your arms are supposed to be little more than a connective link from your torso to the paddle.
This is SO FAR from the normal inclination of the new kayaker, we felt it had to be reported on. The differences in speed and ease of reaching a dive site are enormous, as are the consequences in terms of increased stability due to proper technique (versus some of the intuitive paddling styles which create poor stability and waste energy). Using a normal athlete's "intuitive" style of paddling, when first exposed to kayaking/surfski paddling, an average speed of 3.5 to 4 mph can be considered maximum cruising speed for 30 to 60 minutes. When this same person is provided with a wing paddle and proper technique, paddling speeds of 6.5 to 7.5 mph will occur at similar or lower exertion levels than before.
Further, the typical reaction of a new kayaker to a racing sea kayak or racing surfski is that these elite boats are nearly as tippy as a floating log----but given the proper paddling technique, aided by the wing paddle, these same novices quickly feel enormous changes in stability and ease of propulsion.
Realistically, you can expect that the vast majority of divers who are using scuba kayaks (scramblers, scupper pros, etc.) have never had the opportunity to learn the ideal paddling technique. These same people will all benefit enormously from the Wing paddle and proper technique, even on the much slower hull speeds of scrambler type boats (4.5 to 5 mph versus 8.5 to 9 for racing surfskis or racing sea kayaks). They will be able to paddle faster, farther, and with less effort. And when they get a chance to get on a "rocket" like one of the surfskis pictured earlier in this article, the paddling style they have adopted will allow a much easier transition, and the surfski will feel fast without feeling tippy.
As an example of becoming comfortable in a horrendous current with huge nasty waves coming from all directions, we have shot a video of an elite surfski paddler (using a wing paddle of course) passing through the worst inlet in South Florida, the Boynton Beach Inlet (considered to be non-navigable by the Coast Guard). Currents in this narrow channel, at tidal change, can exceed 8 mph. Large standing waves are thrown up by the speed of the water passing over the shallow irregular bottom. Large Power Boats traveling at high speed to go in or out of the inlet, create huge wakes which bounce off of each side of the inlet, and create huge chop worse than you will ever see on any dive day on the ocean.
The surfski paddlers seem to be better able to handle these extremely rough conditions than all but the largest boats which can pass through this inlet. Normal dive kayaks like the scrambler designs, or even the Scupper Pro would have no chance of traveling into this inlet on an outgoing tide---while the surfskiers consider this great fun!