My wife and I sailed on the Adventure of the Seas in January 2015. We arrived in San Juan the day before the cruise and stayed at the Sheraton near the convention center. The hotel was good but not too much around it. We took a cab to Old San Juan and joined the party that was going on! The San Sebastián Festival was on that weekend which takes over the streets of San Juan. A great time was had in Old San Juan before the cruise even started and would go back to San Juan to experience more especially during festival time.
The Sheraton is very close to the Pan American pier where AOS sails from. We arrived around 12. The line was not too long but was initially slow as the baggage handlers seemed to be arguing with each other and the bags were piling up. Once that was straightened out it we were quickly on the ship with that awesome 'bing' sound as they scan your card.
Our room was an balcony room on deck 7. The room was in good condition and this was the first balcony we have had (out of 4 previous cruises) and we really enjoyed it.
Good room. Loved having a balcony.