The HE-560 can be somewhat boring because for the most part, it is neutral sounding. If you are looking at a more "colored" and "more bass" try looking at the HE-500. I dont know much about the Alpha Primes, but I have owned the HE-4, demoed the HE-500, and currently own the HE-560, and I would rank them as about all the same, but different beast for different music taste. The HE-4 and HE-500 have a smaller soundstage so you get more "intimate" with the music you listen to, and don't particularly work well for gaming and movies (simulated surround). The HE-560 seems a bit boring and underwhelming at first because not any spectrum frequency stands out. But it seem to have a much wider soundstage and much more airy than the HE-4 and HE-500.
The one thing that I really like about the HE-560 is the quality of timbre. When you listen to live recordings, you can identify the coarseness (texture?) of a singer's voice, identify the quality of the bass, the quality of the drums, etc. It just adds to the overall sound that never seems to be captured by technical measurements. The bass quality is a very odd beast. In some songs it seems a bit weak, but whenever I listen to my Motown or R&B collections, the bass hits heavy and satisfying.
You won't go wrong with the HE-560 IMO, but you should demo for your own music taste and what sound signature you prefer. Don't overlook the HE-500 (If you havent tried that already).