We chose the June Baltic cruise on RCCL because of the itinerary (3 days in St. Petersburg, and beginning and ending in different ports). This was our second RCCL cruise, and compared to other cruise lines, it was just okay.
Some positives - food was good, wait staff for traditional dining was excellent, and room was good (lots do storage).
The negatives - VERY expensive drinks, entertainment was mediocre at best (3 of the nights entertainment in the big theater was the showing of a movie - give me a break!), and the whole "pay extra for food at the regular dinners" (not to mention the specialty dining rip-off). Good thing we were off the ship for most days. The Internet was also a joke - $20 a day and most days you could not connect.