Great review man! The B100 is surprisingly good.

@B9Scrambler thanks. It's definitely a keeper.

Hi Crabdog. How much of an upgrade is this over the ZST's or the Piston 3's? Also when I asked a similar question, somebody recommended the Massdrop X HIFIMAN RE-00. These have been hyped to super hype overdrive, especially in one review. http://www.head-fi.org/products/hifiman-re-00/reviews/17132 Maybe you should check them out. 

@GuywhoLikesHIFI it's a different kind of sound compared to ZST. More coherent in its presentation. Piston 3 I haven't heard. I guess for the the B100: clarity, detail and smooth transients across its dynamic range.