Depending on the item being looked at, 10-30% less in the norm in HK; dunno about Korea/Japan. Be aware though that on many items, the U.S. importer won't honor the warranty on "imported" ones, even if it was you personally importing it - Futaba is one of those known to be that way. Thus, the $400 4PX in HK is a $400 no-warranty one whereas the $440 (after coupon) one from Tower is easily returned/repaired if there is an issue.

I wouldn't be bringing the "empty suitcase" in other words. Great for a hard to find in the U.S. Tamiya part, even better for drifting car parts not otherwise imported here, not the real bargain hunters paradise you might imagine it to be.