A screen door required repair in North Epping today. It unsuprisingly had a cheap "wafer" cylinder in it. Beware of how easy these are to force open. Handymen and builders often save themselves a few dollars by installing these 'el-cheapo' lock cylinders with no regard for safety and security when the house is being built.
Brass pin tumbler mechanisms are the only way to go on residential locks. To often I see break-ins from wafer locks being forced with a screwdriver.