don't be to quick to go with what one agency say's is the only and best way of doing things. Their is alot of gear and gear configurations out now. And when you go buying tech gear it is expensive, and so is the training. Talk to active divers, go out to dive sites and see what divers are using. Don't take anyones word as gospel. look at all the agency's GUE,NSS-CDS, NACD,ANDI and TDI to name a few. IMO it is importain to take tech class from someone who dose it for a living full time. I took my cave class form an instr. who makes his living doing it and has done it for years. He is in the cave at least 2-4 times a week. can't beat that kind of experience.