Walter may be your best, 'man to go to' with this. Perhaps PM him in case he misses the thread ??
I'm not clued up with FTTH, but as with any product/service I buy into, I'm not so much interested about the here and now, how wonderful the product is, what it can deliver, etc etc.
What I want to know about, is what happens when things go wrong ?? Lead times to repair both minor and major 'outages', what your rental covers, and the cost of replacement equipment if damaged by the EU.
As I say though, Walter will probably have the best questions, due to his knowledge with B4RN ?