Org is a winner. I have several profitable domains in .org but they are all very Org-centric. I find that if the content matches the extension, it works great. Of course Google doesn't view .orgs in that way but I think it helps in terms of CTR and memorability for the visitor. Orgs do not sell as well on Sedo or Snap, but they do attract clicks and revenue.
If you site is sales based or not in a 'helpful' or 'informational' genre, then .com or .net would be in your best interest.
Of course if I had the choice I would always choose .com.
Just a personal perspective.