The discussion over on MTBR concerning problems with internal cable routing is most likely the fault of the user and not the frame. As was discussed, using good quality stainless cables, applying cable lube upon installation, properly maintaining the bike, and storing it inside are all things that will prevent many problems one or two people are complaining about.
Certainly running the hydraulic brake lines internally is nice since there is no chance of having any cable pull issues there. For my IP-036 I even ran the rear derailleur cable with a full housing through the frame so again no chance for any shifting issues there.
On my IP-056 I also have all internal routing and the shifting has been flawless for over 16 months of riding. My point being is if there is one or two people, out of hundreds of users on MTBR, complaining about a problem you need not take it as fact when they blame the Chiner frame as the source of their problems.
As for the IP-106, that's a really nice looking frame. It has end caps for the internal routing so it looks even cleaner at the cable entry points. However I prefer not to have all those cable mounts riveted all over the underside of the frame. Like me, you are doing a 1x setup which means several of those cable mounts will not be used.
It would be nice if XMIplay offered a 1x specific version of the frame w/o the cable routing for a front derailleur. For me that would be perfect. I have noticed that not even the big name brands charging $10k for their top of the line XX1 equipped bikes are not 1x specific. Given the price, I would expect not to have unused parts on my high end bike.