My favorite example of extreme subwoofer-ism is the Krell Master Reference, with two 15" drivers with a 3 inch excursion. That fucker weighs 400 pounds. Text used to read thusly.
Response #1 -- I think you'd do well with either one, but you'd have to like cats in Hirsch's case (and before you even ask, yes, cats like elephants).
Response #2 -- we live in an international market these days, so we're all virtual neighbors!
The Sunfire is a long-throw, so it still has displacement.
Displacement is volume, not area.
I would definitely do a Sunfire again (I used to have a True Sub Jr.).
I also prefer the continuous phase, rather than a 0/180 switch.
I don't know if the SVS that I am lusting after has a long throw driver -- that might throw me back into the Sunfire camp.
You ever go by the meat market in Laurel on Main St.? I haven't been by there recently, so can't say if they are still so, but they used to be really good.
(makes a mental note to swing by there next time)