Can't help with the food situation but we have some reviews here:- http://www.holidaytruths.co.uk/reviews/spain/balearic-islands/ibiza/san-antonio-bay/costa-sur-hotel-and-sol-post-apartments/

I stayed in the Sol Post apartments 4 years ago which are part of the same complex and abpve the Casablanca . I don't know if they Costa Sur restaurant serves lunch however the Casablanca serves food all day. I holidayed in San Antonio Bay in July this year although I stayed in a different hotel. I visited the Casablanca on a number of occasions for the entertainment and noted the food prices and they look really good value for money and there were plenty of people eating there. You can also get takeaways which in my recollection were also good value.

Booked here the beginning of this year for the middle of September, read the recent reviews which appear dire (many thefts, noise, etc), my wife is on a downer now (not unusual :)) I told her maybe it was just June that the idiots visited the hotel as the reviews I'd read earlier in the year were fine, anyone tell me something good?