I saw some at a ClubCobra NoCal breakfast and in showrooms (e.g., SF Sportscars), and some of the FFcars and ClubCobra members were nice enough to invite me over to see their cars. Once I saw them in person, I narrowed my search to ERA, CSX, and Kirkham as the looks and quality of those three really appealed to me. The main reason I'm doing this project is to do it with my three small children, and the only one of those three that you build yourself is ERA, so I went with that. I've been building it for about a month now, and I'm very happy with the quality and customer service of ERA. If I were to buy a pre-built one, price independent, I think my order would be Kirkham, then ERA, and then CSX. BTW, Brent at B2 is building me an all-aluminum (Pond block) 427/482 solid roller FE. I considered FastEFI 2.0 but ultimately went with a carb. More details here
Lippy's ERA #797 build log. PM me if you want to chat.