RWS /RUAG does produce quality brass for the 280.Rem. But i guess you have'nt tried it.
And if one is to use the 280.AI there are chamber variants that fits necked down Lapua 30-06 brass.
RWS doesn’t make brass for the 280 anymore. The other company you mentioned never heard of them. And using 30-06 brass for a 280 is stupid too because the length of the case is like 50 thousandths less than a 280. And nobody is going to go out and buy special reamers to use 30-06 brass in a 280. That's retarded too IMO.