We were not due to go to this hotel but ended up here after a few problems with our travel company. The reviews on the Bon Sol had worried us, but apparently we had no option so we held out hope that the Bon Sol Prestige would be different. And it was! We turned up to find that the Prestige were brand new apartments, it opened about May 2011. Although the reception wasn't yet at the hotel (requiring a short walk to check in at the Bon Sol - it was finished by the time we left), check in was straightforward. The apartment was very clean, modern and had all of the mod cons required for a self catering apartment. If I was going to be really picky I could suggest a few improvements, but they would be very minor (shower curtain/door is needed and a light above the bath). The pool was clean (slightly too much cholrine) and the pool area was nice (maybe slightly lacking atmosphere but I think that depends more on who is staying at the apartments). The block has its own restaurant, separately owned and run from the apartments, which is good value and has lovely owners. It does mean that you can't take your own food/drink to the pool.
The location is just behind the Playa d'en Bossa strip so is central for the Ibiza life. For the most part it was quiet, although it is next to the Sankey's night club (100m away, separated by a car park and squash courts) which does go on until 6am most mornings. We were in a room closest to the club and we could hear a muffled beat from about 1-6am. A pair of ear plugs would sort this for any sensitive sleeper, and I doubt you would hear it at all if you were on the other side of the block.
All in all it was above my expectation, and better than most of the other apartments in the area. Because of the change to our original booking I can not comment on the value - we paid the same as we would have for a 2* down the road. But on venue itself, very good.