It would seem that it's a bad decision by the Chinese to fund/build this design since the first projects using this design are many years late and many billions of dollars over budget (and still not operating)... but, of course, it doesn't seem to be possible to build a nuclear reactor anywhere near on time or budget. The problems with the EDF reactors cover the gamut from structure (concrete and steel) to mechanical (valves, etc.). Of course, they are developing a new, enhanced, better, EPR design which promises to fix all of these problems... want to bet?
As for pebble bed... good luck with that. It's a new unproven design. Only one prototype has been built (Germany) and it closed due to many problems:
No possibility to place standard measurement equipment in the pebble-bed core, i.e. pebble bed = black box
Contamination of the cooling circuit with metallic fission products (Sr-90, Cs-137) due to the insufficient retention capabilities of fuel pebbles for metallic fission products. Even modern fuel elements do not sufficiently retain strontium and cesium.
improper temperatures in the core (more than 200 C above calculated values)
necessity of a pressure retaining containment
unresolved problems with dust formation by pebble friction (dust acts as a mobile fission product carrier, if fission products escape the fuel particles)