You asked
Is the canon rf 100 400mm f 5 6 8 is usm good for travel?
Here is what the site says about that.
From Canon RF 100-400mm f/5.6-8 IS USM: Canon RF 100-400mm f/5.6-8 IS USM: A zoom lens by Canon for Full frame cameras, 100-400mm f/5.6-8. Light and cheap reach; dim at the long end, so it wants good light. Specs - Maker: Canon - Focal length: 100-400mm (zoom) - Maximum aperture: f/5.6-8 (it gets darker as you zoom in) - Made for: Full frame sensors - Mounts: Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Canon ...
From Wildlife and sport: My picks: - Starting out: an APS-C mirrorless body with a 100-400mm-class zoom. The best value reach there is. - Hiking and travel wildlife: Micro Four Thirds with a 100-400mm. Light, long and stabilised. - Serious sport and birds: a full-frame body with fast readout and a 200-600mm or 150-600mm zoom. Buy used: long lenses hold their value and change hands a lot, and the savings are large. See buying used.
Quoted from this site's pages.