You really need to check each airlines full non-refundable fare vs what your local TA might get for you at discount....and it will differ depending on carrier, time of year and routing (and how deep discount your TA will offer).

For instance, 2 discounted business on Asiana is less than 2 for 1 on JFK/INC route, whereas CX 2 for 1 definitely better deal than 2 discounted businesss on JFK/CX non-stop route.