Would like to provide an update: I actually got to meet Cesar Aguilera (owner of Portaphile) last week.
He brought his own personal amp to my house and loaned it to me for several days; even offering to let me take it on the road for a few. Before picking it up yesterday; we chatted.
Having never written a review before; here goez (sic).
Gotta tell you; this is one heck of a good amp and Cesar is one heck of a great guy!
I tested it using an iPhone 4s, EASE LOD, Westone 4R's (stock cables - haven't gotten around to swapping them out for my Chris_Himself's recable mod) as well as the cans found in my sig.
A-B'ed the 627 against Amped Up's cmoy, FiiO E11 & Gary Ali's PA2V2.
What I noticed was the 627 was appreciably louder with a much broader soundstage (especially on live recordings) and tighter bass than the other amps.
I heard things in the music I had either never heard before or became more expansive as well as defined; eg., the opening of the (live) Eagles "Hotel California".
Please see the attached playlist for the songs I listened to; also the new Paul Simon "Live In New York" album.
I would like to personally thank Cesar for providing the opportunity to audition such a quality product.