I have not had the same luck as the other replies here.
We stayed at the Palladium Royal Suites in November. We emailed the resort 1 week ahead with our request for an upper floor suite in building 50, but got a ground floor in building 52. Went back to the desk and Octavio told us he would change it in 48 hours. We did as he asked, and as we entered the lobby he calmly walked out of the lobby. We tried again a few times to talk to him but he kept doing this. Once we caught on to the fact that he was avoiding us, we left it alone.
The ground floor felt safe. Security walks the grounds all night.
If they give you an upper room in building 52, You should insist they change it to another building. The entry door side of building 52 faces the wall that divides the resort off from Cortecito (the patio doors face the pool; in fact all the patios face the pool/ocean). If you are on the 2nd or 3rd floor, you will be above the wall and it can be quite noisy, but as we were below the noise, it was not bothersome, except for the occasional noisy muffler, but nothing woke us up in the night.
We did have hot water problems in building 52, which is consistent with what I had read in reviews. We got the hot water fixed as soon as we asked, but it never did get hotter than a good hot shower on 100% hot but that was good enough for us. Always cold in the morning though.
If I were you I would make the upper floor request in building 50. It is across from building 52 and is also close to both the beach and pool. Building 51 is the one that houses the lobby but is the furthest from the beach and pool and is between 52 and 50, forming 3 sides of a rectangle, with the beach being the other end, if you will.
51 is not that far from the pool/beach maybe 50 more steps to the pool. But you would have less music noise from the pool area in that building, but as close as we were, it was not bothersome. The white noise from the AC washes it away. The music is not played loud at the RS anyway.
Have a great vacation there, we did.