I've been thinking about buying a Sekonic light meter and I've got a few questions. 1. Do you feel it's made a cost justifiable difference in your photography? 2. I'm wondering how it deals with that fact that a given ISO differs from one camera to another? 3. All the on line references always show it set at ISO 100. Just curious why this might be? 4. I'd be using it primarily for outdoor work. Most of the references seem to suggest it's a more valuable tool for studio / flash photography. Is this true? I'd appreciate any suggestions, comments and references to on line resources. Many thanks & Happy Holidays!