A watch is worth whatever YOU are willing to pay for it.
Phong sells alot of nice aftermarket parts, but he also sells alot of highly questionable parts at near-gen prices. & there is little consistency to them. His pre-assembled watches tend to look pretty good (not 1:1 exact copies of gens), but, from those I have seen, they tend to be of shoddy condition with missing/broken/worn screws, missing/broken parts epoxied together, etc. Unfortunately, the same can be said for just about any other pre-assembled franken from any of the other 'high-end' sellers. This is not to say you should never buy 1 of these frankens, but it is important that you do YOUR research on the gen & know what you are getting into before you click the buy button.
This is a good case for the old 'if you want it done right, do it yourself' adage.