Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.1030 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
"US domestic F is never worth the 3x considering it's not true international F."
Well, it might be worth it to the OP, who was willing to pay $980 USD for a roundtrip cash ticket in F. An Avios redemption would give him slightly better than 2.1 cents per Avios in value (but without earning tier points or Avios on the reward flights).
On the other hand, if the OP can get some other redemption he wants that will yield a value of more than 2.1 cents per Avios . . . .