Import duties etc...thinking of buying a Daytona in Japan / bringing back to US

[Speed]

OK, so there is a bit of a plethora of Daytonas (a few more black than white, but both available) in Japan. These can apparently be purchased "duty free" which seems to mean about a 4.5% "reduction" in the listed purchase price.

The new V series seem pretty spendy - approaching $12K US after currency exchange...but used a bit better / and more to choose from...M, F series and older.

I think I actually prefer an older model - no ROLEXROLEXROLEX on the rehaut!

However, I still think that the customs folks slap another duty on if you bring it home / declare at your port of entry in the US.

Questions:
1. Does anyone know how the duty would work on a "duty free" Daytona purchase?

2. Am I correct to think the Daytona market still seems pretty tight. BTW, I am leaning black dial Vs. white now. After trying on a white, it just did not seem to pump me up...but the black...

I would likely not consider buying a Rolex in Japan were it not for the relative scarcity of Daytonas in the US - even among TRF sellers

Thanks!