We stayed at both Ebony and Lebombo, and visited Boulders. I don't think you can go wrong with any of them - they will all give you a fabulous experience. Lebombo was very new when we were there two years ago, and the animals were not used to the vehicles. This gave it a little more of a wild feel than Ebony. We saw plenty of animals at Lebombo, and the highlight was driving into the middle of a pride of 21 lions. We arrived just before sunset, and stayed until well after dark when all we could see around us was the glint of light from their eyes as they prowled around us. It was an unbelievable experience. If you should decide on Lebombo - ask for Piet as your guide. He grew up in the park - his father was a ranger, and he had a knowledge and feel that were unsurpassed with any other guides we encountered.
The food at both was superb, and the staff could not have been more helpful. Whichever one you choose, you will have a fabulous time. I'm so envious you're going!