Buying used: NYC 47th street or Internet?

[Alien1]

Hello fellow watch lovers!

Let the fun begin... I am looking for a used Rolex DJ. I've been monitoring the forums sales, but it seems that I can wait for a year before the exact model I want comes up for sale. So, there are a couple of choices I see:

1 - NYC 47th street. I once jumped into one of those places and was pretty impressed with the price and the choices (the seller offered to swap the watch dial with any one of the 30 genuine Rolex dials they had).
Likes: seeing all the potential surprises before buying (scratches, bracelet stretch, etc.).
Dislikes: no warranties or any guarantee the watch works and won't require a $500 maintenance right away.

2 - Online retailers. I read good things about watchchest, santblanc, and essential-watches.
Likes: Warranties they offer (1 to 3 years, guarantee of perfect time keeping)
Dislikes: not handling the exact piece I buy (but I think there is always the return option).
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So here are the questions to the experienced buyers:

1 - which option would you recommend?
2 - what stores on 47th would you recommend?
3 - what sites would you recommend?

Thanks a bunch!