Like you, Rianie, we usually treat ourselves to a top restaurant (we prefer lunches) and you will not be disappointed at Le Palm d'Or. For years we resisted, because we stay pratically next door, and considered it a "local standby"; we usually went further afield. But two years ago we gave it a go, and it was so good that we repeated more or less the same thing this past summer. Indeed it was pricey but the food and wine (impeccably matched) is a wonderful experience. So too the service.
BTW, we are very lucky to have SOOOZ in this forum to so generously check out "what's what" in Cannes and update us!
Another very good restaurant, but not as upmarket, is La Mandala across the Croisette on the beach. Great food, friendly service ~ I usually have their Degustation ~ never disappointing, and the atmosphere is entirely relaxing.
Hope you have a great weekend!