@big_greg - I really loved the P3esr's and never thought I'd move on to something else, but here we are. When I was in a smaller room and seated about 5 feet from the speakers, the P3s were very satisfying. However, once I moved to the bigger room and sat about 8 feet from the speakers, they just couldn't keep up. Also, my Blackhawk was never able to drive them all that well.
The M30.1's, in my opinion, build upon the P3esr's with better scale, dynamics, and go deeper. They're also better for low level listening, I can easily hear more details at low volume. They're also an easier load for the Blackhawk. As I mentioned before, the way the sound leaps forward from a dark, quiet background is something to behold. But I think if you're listening near field, i.e. 5 feet or closer, 30.1 might not be that much of an improvement. They definitely need more space around them. Now, when it comes to human voice the 30.1s are superb, much better than my Olympica IIs, but I still think the P3s hold a slight edge.