Has anyone heard Wadia 521 DAC?

Just wondering if anyone has heard the Wadia 521 and in particular used direct to amp? Impressions on sound and ease of use would be appreciated. Looking at going without a preamp and driving a McIntosh MC402 direct with this DAC. Unfortunately I won't get the chance for an in home audition. Have only heard Wadia products once (not sure which model CD player) and was favorably impressed. Thanks for any info you all might have.