I think $12500 is too expensive, and for a complete bike with Di2 I would rather take the Giant Trinity Advanced SL 0 or the Shiv (even though not Di2 optimized).
In fact I did and have both bikes (from my friends at RA Cycles).
My view on Felt is that they have some fantastic value bikes in their range, but the 2011 DA is too expensive compared to the competition and the drag numbers.
If the option was for a frameset then I would rather have a Shiv or a Trek SC. The Trek SC has more lust factor for me than a DA.
Ultimately the consumers view is the one that matters and my feedback for SD is that it is too expensive. Also the aero numbers for the DA compared to the competition “appear” to not be as good and they have not released anything unlike Specialized and Trek except against the old DA.