Does Charter cost more than airline flying?
This depends. With charter you cannot simply compare the cost of an airline ticket to the investment made into a charter. In the case of high net-worth individuals losing valuable productivity time very often means losing more than is saved with an airline ticket. In the case of celebrities, people requiring security, access to difficult to reach and out of the way places, airline flying due to the security complexities, limits of routes and schedules ends-up being more expensive in the end. You need to compare your situation to the alternatives.
Is charter safe?
In most cases, charter is safer than flying on a scheduled airline. Apart from being strictly regulated, charter aircraft are often flying less hours and being observed more due to downtime versus their airline counterparts. Now add to that, the fact that charter does not appeal to people making political statements or other human related security issues and it is a clear indication that charter is as safe as it gets.