What you use depends on how long the engine will set before you start it. The liquid assembly lube is really good stuff, but will run off over time. It will leave a coating behind but most of it will be in the oil pan in a week if you wait to long to start it. This is assembly grease, http://www.cam-shield.com/acatalog/CamShaft_Assembly_Paste.html
, black moly with ZDDP additives. It will not run off, but like all other assembly lubes, it will get wiped off if you rotate the engine enough. White assembly grease will also hang on, but it doesn't have the ZDDP the grease does. For stock valve springs and camshafts, white grease should be fine. I also like REDLINE assembly lube, https://www.redlineoil.com/assembly-lube.
I have used all the above and have had good luck with them. I like the black grease on cams, the Redline on the valve train, and white grease on bearings, I also use break-in oil from PennGrade oils. When building customers engines, I don't like warranty work so I do everything I can to break them in right.