The amount of bounce needed depends on conditions. If you play courses with soft, fluffy sand, you'll need more bounce. If the courses you play typically have harder sand, you'll need less bounce. Playing from fairway - less bounce.
The type of swing can influence the amount of bounce needed, too. Players who swing their wedges steeply into impact need more bounce. Players who sweep through and undercut need less bounce.
For more, see the FAQs:
What is bounce?
Do course conditions and swing type influence how much bounce I need on my wedges?