My husband and I had cruised once before, with another cruise line, on a big ship similar to the Epic. We wanted to give Norwegian a shot just to make sure we weren't missing anything. Embarkation was very smooth (as was disembarkation-no problems either time), but I was already a bit put off that I couldn't reserve everything (e.g. boat tour, some entertainment) ahead of time online, so we had to waste our time onboard the first day booking things instead of getting in the pool.
The good: we got a thermal spa pass for the week and it was a WONDERFUL place to relax away from the crowds. Heated pool, saunas, steam room, peace and quiet! There was one super friendly woman who worked at the buffet spraying hand sanitizer (the "washy-washy, happy-happy!" lady) who was always upbeat and smiling. "Priscilla, Queen of the Desert" was an awesome show! The food in the specialty restaurants was really great, especially the Brazilian steakhouse and the Japanese steakhouse. The fitness center was pretty nice, too.
The bad (pretty much everything else) :
The cabin was spacious with a nice-sized balcony and a quite comfortable bed. It was quiet enough, even being near an entryway (I think it helped that it was right off of the spa area.) I didn't think that the weird bathroom with just a frosted door for the toilet (and a privacy curtain) would bother me, since I was travelling with my husband, but we found that it made us both very uncomfortable. For this reason alone I would never cruise on this ship again.