wardric:Yep.
some quarry dives need and develop more skills than calm shallow reef dives. For example, we have a quarry close, depth over 250', temperature year round is in the lower 40's under the thermocline, with some artificial wrecks and fish. If you only dived tropical reefs, you should find some nice challenges on that site.
Absolutely. The viz in our local (within 3 hour drive) quarries is all over the place (depending on the depth, and site -- complete blackout in some, at depth). In one quarry it averages about 10-20 feet, but clears to >60 feet at 100 ffw depth. However, it can be the best way to do the low-viz checkout in AOW, and get your navigation skills down. Clear (and warm) "open" water can seem like a walk (or kick) in the park, after a quarry dive...
No doubt it should be logged...