The M3s drives the P1 without issues using either the single-ended or balanced output, and the P1 is not a particularly sensitive IEM so there are no noise floor issues. As I mentioned in my review, a well-designed and implemented source device, which I believe the M3s to be, should be transparent. I review DAPs mostly for UI, features, and power. Your mileage with the P1 will depend much more on how you like the inherent characteristics of the P1 than anything else in your chain. Hope this helps!