Has anyone ever purchased camera lenses new or used internationally from local camera shops? Is it worth it?

I'm looked at a Nikon 70-200 f2.8 and comparing prices with B&H the local shop has it for roughly $500 dollars less.

I assume the new lenses are all "gray market?" But would it even matter with used lenses as long as you were able to test their function?

I can't help u with that, but how do the Nikon Refurb lenses compare?    On some items during their sales, they do even better than the typical 10% off.   And they have a sale almost monthly it seems.

I buy cameras and lenses from Japan on occasion.  I've never had a bad deal.  I did get one in that was damaged slightly in shipping.  I let the seller know and he (mapcamera on ebay) sent me another lens to compensate for the damage even though I never asked for that.  I just wanted to let him know that the lens was cosmetically damaged in shipping and that I knew it wasn't his fault.  

I did get one bad deal from a seller in Europe who was a complete asshole.  He sent me the wrong lens and wanted to refuse to take the item back or send the right one.  I had to escalate to ebay to get the issue resolved.  

But for the most part, I've had very good dealings with sellers overseas.  If you do ebay, the trick is to find a seller with a lot of reviews and 98-100% rating.

If there are issues they're what you'd expect buying any gray market item.

If you're comfortable with spending hundreds or thousands on something with little or no warranty support or customer service.

Yeah, the gray market cameras and accessories are what I’d be afraid of.

Grey market= problems with warranties.

If you're not concerned with that, you should be gtg. I had a Canon 1DX that I bought in Europe that ending up totally bricking. Canon USA eventually took it back to fix, but I had to provide a ton of paper work that it was actually a legitimate buy from a licensed EU dealer. I would avoid it if I could.