SSi's get very loud and will handle 3k no problem. I really do not see a comparison here. The SDCs will get louder then Type Rs, we put terrible amounts of power to SDC that would have ate Type Rs in no time. We ran a Cadence ZRS-9000 to a pair of 12" SDC and pulled a 151.2 in a trunk car. But hands down the SSi, they will get louder then a Type R, handle more power, and sound better. An SSi is more comparable to a Type X if anything. Type Rs are nice for the money but I just do not see any comparison. I truely hope everyone offering up opinions are from experience with all 3 woofers. I have had my fun with Type Rs but they do not handle lots of power over long periods of time.