Difference between Schiit Modi Versions


I own a Bifrost Multibit- which I love to bits.
I am putting together a small office stereo system, and need another DAC. The Modi is inexpensive and probably more than enough for my needs.
My question is:
There are 3 iterations of this device. Standard, Uber and Multibit. I emailed Schiit, but they say they don't comment on sound reproduction.
So, I am asking the Agon Community to help clarify the differences between the different models, if possible, and help me make a decision as to which one I should buy.
Thanks Bob
gdnrbob
I agree, my Bifrost Multibit is unbelievable, as well.  Has me listening to digital music seriously for the first time in my life.

I would definitely go for the Modi Multibit

-j
Thanks docknow, I agree, the Bifrost Multibit is unbelievable. I have been using mine daily since I bought it. In fact, I don't even play my CD's anymore. I would get another, but this is just for my office and I wanted to save a few bucks.
Is there anyone here who can explain what is the difference between the three versions or know where I can read up on it?
There's only two different dacs, the base Bitfrost which is Delta Sigma based Wolfson  conversion. 
Or the more expensive the Bitfrost Multibit, which as the name implies is Multibit Analog Devices conversion.

There is Bitfrost upgrade cards to old Bitfrost models.
Cheapest again the Delta Sigma 4490 card $100.
The more expensive Multibit AD5547 card at $250
http://schiit.com/products/bifrost

Cheers George