First, I heard them while in LA in late June in an HT setup with Emotiva. From what the host told me, Hsu headquarters were just 15-20 min from his home in Orange County. To me they sounded very similar to Klipsch with a slightly smoother treble.
In NO WAY do they compare to the Studio 20's, they lack the weight and presence for starters. They miss the second level of detail that one finds in monitors around 1k.
The Titans from memory I believe, have better consistency across the entire frequency bandwidth. But it would be a fascinating comparison.
Go hear the Hsu's to satisfy your curiosity, but IMHO you're taking a big step back from either the Rainmakers or the Studio 20's. If you hear the Hsu's at their headquarters, keep in mind that like all manufacturers listening rooms, it's been setup to show off the best qualities and minimize the weaknesses.