i went ahead and decided to go with digital desings and as i was lookin over them some one said i should try the 9900 series are they louder then the 9500 series?
are you a pro class SPL competitor in burping events? the choice of sub is only a small portion of making a system as loud as possible. Most people for daily driving musical use can use nearly any sub or pair of subs to get a system well beyond the pain threshold.
Getting loud is going to be dependant on the enclosure and power you're running, which then is dependant on your electrical upgrades. All needs to be up to par together.
pointless to get the 99 unless your a hardcore competior and have unlimted power. your probally better off getting the 3500's two of them with a nice 2500-3000wrms amp and a GOOD box should be more than enough to meet your needs.