personally I flew with them once back to Italy (actually we did a stop first in the UK, then went back from Milan). The airplane they mostly fly to TPE is old, but this is relevant only if flying business class (the dreaded middle seat like old Emirates 777s).
I liked the food, service is ok, prices are getting steep indeed, but can still find some decent deals. IST airport is a cash grabbing machine for the government to get as much foreign currency as possible due to the laughable value of the Turkish Lira now. DO NOT BUY ANYTHING AT THE AIRPORT!!! Lounges at IST are fine.
I hate they don’t have premium economy at all…