Yes, best to spend only $10 dollars if you are looking for a bit of a sleep. I went with a friend to see Tannhauser in Barcelona. My back problems were kicking in and I had taken some pain killers and muscle relaxants, also some wine. I remember most of Act 1, but waking up at the end of the opera, (there must have been intervals), my friend lent across and said, " Well that was an expensive snooze."
Mike