I think I am a coffee snob. It has to taste really good or I wont drink it. When I sailed on the Monarch of the Seas last summer, I had room service in the morning for coffee. It was like drinking sludge. It tasted horrible. It was the same in the dining room too. I will be sailing on the Mariner of the seas and wondered if the coffee is just as bad. My other option was bringing my own coffee and travel coffee maker. That way I know it will be good.
The free coffee is the same on all RCCL cruises. On the mariner there is a cafe where you can purchase the "good stuff". I agree with you on the coffee. My mother actually liked it but she drinks Maxwell House instant coffee at home so compared to that the RCCL coffee is like Starbucks to her.