Help me decide between the many carbon frames that are available on the market…
Planet-X
Beyond Fabrication
Velo Vie (?)
XLab
Best value? Best follow up if any issues?
Should I be concerned with internal cable route vs. external cable route?
I think that the Planet X and Velo Vie are exactly the same framesets. I believe that the XLab and Beyond Fabrications (and Token too) are also exactly the same (they all have the new cable routing for the RD through the seatstay). External vs. internal cable routing doesn’t make much difference so wherever you can get the best deal on one of these frames that fits you would be my recommendation. I saw an Element6 carbon frame (same as Planet X) on Ebay a few weeks ago for under $900 for the frame, fork and seatpost.
They are all the same. if I were you I would go on Ebay get the cheaper (non-branded version) version and give Planet X a kind phone call and ask a new decal set for your custom painted Planet X bike 
Then sell the darn thing on Ebay and buy a Cervelo
Well, that’s just and idea, I would never do that but just make a research which brand has better customer service and crash replacement etc. You’ll paya few bucks extra maybe for the same frame but it’ll worht it.