Yes, and it's working wonderfully! The Ear+ is a great tube amp, especially as it works so well with low-impedance 'phones too. The MAD amps are reportedly great with Grados (of course I sold my RS1 before buying the Ear+, silly me) but I'd say that pairing one with a Denon is just as great.
Yes it's a great amplifier. I used mine with Alessandro MS-Pro and it was great. Sold mine before getting my D7000 but had the chance to try my D5000 before that.