Diamond D6/d3 Subwoofers?

[2k1prayl00d]

Anybody have any experience with diamonds d6 or d3 subs? I just got back from a sound dealership and they recomended I get the d6 along with a custom ported enclosure they would make. I know that the d3 can handle up to 400 watts rms, but how much would I get running a 1000 watt amp (nitro bmw 482 to be specific.. its temporary lol). And how much would I be getting on a d6? This will be a huge upgrade from the current setup right now, 2 pioneer competitions lol, so I really want to be aware of how much of an upgrade this will be. - Thanks