I have sat in your SC300, if that is what your asking. I think there was a pair of dd 8s, vibe 3 way components, handful of vibe amps, and premier double din.
They didn't really compare to anything I have heard(single 12'') but I think it was cause it was in a trunk.
I have no doubt in my mind that a dd8 will out perform 12s out there. Just didn't really surprise me. I think they might have been in a truck box and that is probably why they didn't blow my mind.