Secret Garden and Blue Rose are run by the same family.
The Blue Rose get more local/european clients who are generally older than the mainly brit guys who go to the Secret Garden. Secret Garden does get the San An beer boy crowd.
Take lots of money, the girls are very skilled at relieving you of it! There are a few more clubs round the island but they are a little more 'shady'.
If you're going Ibiza town then its quite good to go Blue Rose and then Pacha. Then at least you wont stay in the strip club all night spanking all your cash!