MSilvia:I'd guess the diver used to the added weight, reduced mobility, and general hassle will find the blue water dives much easier than what they're accustomed to (even if there is a lot of chop and current, which can happen almost anywhere), while the tropical diver would feel claustrophobic, task loaded, and out of their element if faced with managing all that extra gear, exaggerated bouyancy changes at depth, 10-15 foot visibility, cold water, etc.
I agree with this. All other things remaining equal, cold, low vis water inherently task loads most divers more from my experience.
If your experienced in cold, low vis conditions, its an easier transition to dive in warm, good vis waters than the other way around IMO.