I've saving for an SVS to replace my current Velodyne CT-120 and wanted opinions on which to get. Since I am having to save to make the purchase, I could probably get the ISD 6 months sooner than the +12. I know the +12 is better, but is it that much ($300 and 6 months) better? My HT is my living room, so it's 20 X 16 with 9' ceilings opening to a breakfast nook and kitchen. Opinions from those who have heard either or both would be appreciated.