I listened for a bit last night with the new Amperex in place and my T1's. The Head 2 is fast, musical, and balanced. The Stratus on the other hand is more romantic and lush, which was part of Donald's design goal. The Head 2 seems to be more linear and has less tube bloom. Bottom line is that I like them both in their own way. Both are musically engaging and satifying to listen to. If you want that tubey warmth and sense of space(that DHT's do so well), I recommend the Stratus. The Head 2 will be a little quicker, more balanced, but also a little drier.
Side note-my Head 2 only has a 1/4" output, so I'm using a 4 pin XLR to 1/4 adapter (thanks WyWires!)