i am in the same boat too. i owned 805s and now have sf concertos. i am very interest in hearing the sig since i have heard a couple of people say they are a lot better then the nautilus. i can't wait till the auditor comes out too. luckily i have a dealer near by that sell both brands so i can ab all 4 of the speakers together. anyone know when the auditor i coming out? i spoke to dave a sumiko and i remember him saying it is coming out in april but when i spoke to the dealer he though it was coming out in two weeks.