RB consumeables will always be a lot cheaper than OC consumeables. The initial cost of the equipment is what most people choke over; however, keep this in mind:
I sold a lot of my OC gear and generated several thousand dollars to put toward the RB. The RB will always be worth something when you decide to sell it. Say no less than 50% based on the prices I've seen on RBW. So if you buy a new Optima and MOD1 training for $7500 and $1500 for a total of $9000, and you apply the say $2000 you got for your sets of doubles and other OC items, then you have a net of $7000. Figuring a max depretiation of 50% or $3750 on the RB, then you only need to amortize the $3750 over the dives you do.
If you are spending $75 per dive more for OC consumeables vs CC consumeables, then the RB is paid for in 50 dives. After 50, you are in the clear and saving $75 per dive. You can always sell a used Optima for at least $4000, so my numbers are conservative in that regard. Heck, buy a used Optima for $5000 and amortize $2500 over your dives.
If your hobby is riding motorcycles, a Harley runs $15K and up. A sport bike, maybe $9000 and up. No difference really.
Adrian, Did you guys do the Lowrance today? I didn't get home from Boston until this afternoon.