It's an awesome dac. No reason to dismiss it. It does nothing wrong and sounds great. Does dsd and auto-switching.
Here is a Tube DAC with replaceable caps that I would love to try-
http://www.musicalparadise.ca/store/index.php?route=product/product&product_id=80
There are some excellent user reviews on it. I like the fact that the Caps are held in place with screws so you can roll the caps as well as the tubes. I would love to try some Jupiter caps in it although the stock Obbligato Golds are excellent and cost about $28 a piece and there are 4 of them. I just may have to buy one to tinker with.