I'll start by saying I have no experience with WC anything. I'll just give you my opinion (I almost always have one!)
PROS
They are usually cheaper (as far as purchase price).
They aren't very likely to be related to CB's so the blood lines
will be unique.
CONS
They are more likely to not thrive.
They are much more likely to have parasites.
Their end cost could be greater than you bargained for.
Their temperments will vary more dramatically can CB.
They might not adjust well to a captive environment.
They must be quarantined rigidly away from your established
reptiles for 3 to 6 months, the longer the better.
You will be supporting the capture and export of the species from
their native land when it's not necessary due to the
availability of CB.
If I were to buy a WC (which I'm not completely against doing) I would want pictures. I would also keep it out of the same room as my established snakes for a very long time. I think the longer in captivity it has been would be better. I would also check out the seller's reputation very well.
Hope that offers some insight, whatever your choice will be.
Linda