Little late here, but I have a VTF-15 and 2 Seismic 110's. The VTF-15 is definitely more potent than a single Seismic 110. The Paradigm is amazing for what it is (tiny), but you could fit 4 of them inside a single VTF-15. I use the 110's in my office and kitchen systems. The kitchen didn't have a sub previously and required a small sub for WAF, and in the office the Seismic replaced an HSU VTF-3 MK III (can you say overkill?) which had previously replaced a VTF-1. For 2-channel and gaming in the office I don't feel like I lost anything, and if anything the bass tightened up a little with the PBK, but in the HT I would only consider replacing the VTF-15 with the pair of 110's, and in that case I would want to have a good listen before making the change final. I was originally planning to buy just a single 110, but the seller had 2 of them and the price was right. I sold the VTF-3 for $100 less than I paid for the 110 for the office, but I'm in Canada and the cost of shipping a big HSU here is about $400.