I don't think the choice is between 105 and Ultegra 6700 because the price difference is real enough.
The choice is between Ultegra 6800 and Force 22 - both 11 speed and both about 40% off rrp right now.
I'd buy Force 22 and sell the brakes, use the brakes from your Pacer on the BMC and buy some cheap/decent second hand brakes for the Pacer. You'd come out with Force for roughly the same price of 6800.
I don't think the choice is between 105 and Ultegra 6700 because the price difference is real enough.
The choice is between Ultegra 6800 and Force 22 - both 11 speed and both about 40% off rrp right now.
I'd buy Force 22 and sell the brakes, use the brakes from your Pacer on the BMC and buy some cheap/decent second hand brakes for the Pacer. You'd come out with Force for roughly the same price of 6800.