Originally posted by martinos I would be happier with some cheaper flash which would be fired through cable or radio controller
In terms of exposure, the light from the built-in flash is negligible when set to be the controller. If you absolutely can't have any light coming from the built in flash, you need a hot shoe mounted trigger, regardless of how cheap or expensive your external flash is. Then if your external flash doesn't have a receptacle for a cable or a compatible built in radio reciever, you need a separate receiver with a hot shoe that you can mount the external flash on. Cheaper flashes aren't more likely to have the receiver built in, so getting what you want (remote firing of the external flash without using the built in flash) will cost you the same, no matter if your flash is cheaper than the Metz or not.