From what I've been reading, the EA113 (TFSI) is better and stronger than the EA888 - Hence why both the 'Rocco R and Golf R are actually running tuned EA113s. Corners and tolerances have been 'trimmed' to make the EA888 cheaper and easier to build. I guess only time will tell whether the EA888 can be tuned to the same degree as the EA113 and be as reliable.
Also, chain driven isn't as fit and forget a people think. Chains still stretch over time.