Hello,
As a basic intermittant photographer I aquired the 25mm 35mm 50mm 60mm 70-210mm and 300mm using an RTS II body. All Ae German, for the purpose of capturing moments in life of my first child. My knowledge is slightly more than what the owners manuals provide.
Some of my best photo's, outdoors, were with the 300mm, I found it's contrast and satuaration of color to just, pop. People would say, WOW what a great photo. The photo's were mostly candid shots made close by the use of this lens. The sharpness and focus were also..well just exceptional.
I used to laugh that I had "bought" my skill and the photographic results. This aplies to outdoor clear day photographs. I found the next lens that became most trusted was the 60mm, again with the same purpose and same great results for sharpness, contrast and color saturation/rendition.
If you value and want to capture the moment by distancing yourself from the subject, the 300mm will deliver. The rich true to life colors produced by the contrast probably stand out most.