hafta das din to nikal hi jata hai easily..
Sync wax say zara zaida protection mil jati hai.. but it depends on many factors such as dust, rain, how much daily drive etc etc..
best way is to wax the car and then keep it clean with detailer spray, it will strengthen the wax and prolong the wax's life.
i usually wax my ride after 2 weeks.. & # 26 is more long lasting as compared to GC.. personal experience!