I think I'd only have one for serious medical issues.
After seeing how painful and slow the recovery is (3 friends have had c-sections) there's no way I'd want one unless absolutely necessary. You can't pick your baby up for ages, can't drive for 6 weeks (even if you feel physically ok to - your insurance company won't cover you if you claim and you'd had a c-section within 6 weeks) breast-feeding can be more difficult, infections are more common, you're more likely to need another one in future pregnancies, and it bloody hurts!