Exemplar Denon 5910 owners

I just bought the Exemplar 5910 player and would like to know what kind of tubes that can be used with this unit. Any impression on the 5910 against others top end players? I tried the search fuction but most impressions are for the Exemplar 2900 and 3910. Thanks.
Call John Tucker directly at 425-334-4733. That's what I did. His customer service is outstanding.