While it may be on the pricey side their desserts and pastries are big, rich, filling, and very attractive. The lines can be long at times but in my opinion it's certainly worth the wait for the quality you are getting. The lines forms a circles around the round main counter so this will give you time to drool over the pastries in the cases to make you decision. There are also cakes on display that look so could you can't believe they are real. They clearly invest a lot of time and patience in their work.
Not only that but they make sure they are always fully staffed. There are several employees on duty ready and willing to help as soon as it's your turn. There is a bit more of a wait if you are ordering breakfast, lunch or crepes so just put your order in and have a seat or come back and pick it up later. You can always go visit the gorgeous Bellagio Conservatory & Botanical Gardens or nearby shops to pass the time.
Don't bother with any other places in the area that claim to be Patisserie's. You will be disappointed. Jean Philippe is the top contender!