From the website:

I interviewed an electrical engineer in January. He’d applied here after discovering the Objective2, and during our discussion, he asked, “What’s there left to design? The O2 is audibly perfect. How can you build anything better than that?”

What a dumbass thing to say. 

Whats there left to do?  I already sucked a bag full o dicks. I realized the anwer was to share that experience with the world. Introducing the nwavdeucherizer60000

My goodness.  Eight pounds of hubris in a five-pound bag.  Where do I go to slap these people across the face with a dead fish?

It was an interesting read, thanks for sharing. I had the C421 for a while and thought it was quite the pleasant pairing with the Senn 598s. The bass boost was a surprise, as I felt it was implemented quite well.

If the C5 is an improvement over the C421 in the same price range, I would say they did a good job. After getting used to the size of the Dragonfly and the ease of plug and play on the go, I'm not sure the C5 is in my future. I wish them all the best though, as my experience with JDS Labs was quite positive.

EDIT: @Quest, I have heard both but sold the C421 off a good while ago as it didn't really have a place in my setup (Preference for O2 due to higher impedance headphones at home, Dragonfly for transportable, DAP alone for truly portable). From memory, it was not an unfavorable comparison for the C421. They did a good job on it IMO. 

I think my irony meter just exploded.