...Keep in mind that you cannot return opened computers to B&H (unless they are faulty out of the box or damaged during shipping), so make sure that you are happy with the configuration you choose of you ever order through B&H...
For something like an iMac Pro, a lot more is involved than making sure you're happy with your chosen configuration. Performance testing, application compatibility testing, etc. are complex and cannot be done in an Apple Store because they can only get the base machine. They are also not configured or prepared for serious, professional testing and evaluation in their store.
I'm not talking about returning an iMac Pro for a frivolous reason such as "I didn't like the grey color". Say you're a professional video editor and when testing your company's post-production FCPX workflow you immediately discover that the iMac Pro is 35% slower than an iMac in certain cases because of inefficient H264 hardware acceleration on certain codecs. That cannot be determined ahead of time by reading casual, frivolous reviews by vloggers.
This happened to me, but I am generally otherwise satisfied with the iMac Pro and don't need to return it.
It's very quiet, generally very fast and a good fit for our film post production. Apple will probably improve transcoding efficiency in the future as they optimize use of AMD's UVD/VCE hardware. However -- just out of curiously I discussed with B&H if it could be returned -- they said no.
They then said they might possibly make an exception and charge a 15% restocking fee. Fortunately I didn't really need to return it, but had it been a little slower in a slightly wider range of conditions I would have wanted to return it.
I strongly recommend anyone contemplating purchasing expensive Apple hardware such as an iMac Pro consider seriously the return policy of your retailer. The potential tax or shipping savings if buying from B&H are much less than paying 15% restocking and insured return shipping on an $8,000 (or more) computer.
It currently appears Apple Store, Best Buy and Micro Center permit returns with no restocking fee. The other retailers either do no permit returns of Mac computers at all, or charge a 15% or 20% restocking fee.
Abt Electronics: 15% restocking fee
Adorama: no returns of computers permitted
Apple Store: returns permitted, no restocking fee
Apple Refurbished Store: returns permitted, no restocking fee
Best Buy: returns permitted, no restocking fee
B&H: no returns of computers generally permitted; on a case-by-case basis they may permit returns with a 15% restocking fee
MacMall: returns permitted, discretionary restocking fee
Mac Connection: returns permitted, minimum 20% restocking fee
Micro Center: returns permitted, no restocking fee