At some point we all reach saturation with what can be gleaned from the observations and impressions of others. When that happens there just is no substitute for actually handling and viewing through a few of the top candidates. Even though they are all first-rate, the top binocular brands all offer their own blend of features, handling and image characteristics. The viewing experience through a Leica, Zeiss, Swarovski, etc will all be markedly different and only you can decide likes and dislikes. You also didn’t mention what they’d be used for and in what kind of environment.
You mentioned wanting to know the difference between the SF and SFL. Yes, the SFs offer a smidge crisper view and have a smoother focus mechanism than the SFL. The SFs are notably larger but very well balanced and feel light in the hand. However, the SFL is no slouch. I love its very easy and beautifully colored view and they are much more compact and lighter than the SFs. The 8x40 SFL is my go-to glass for the woods. The Kowa 8.5x44 offers very crisp views but to me they are a bit bulky and heavy with tight eye relief. I also own a 42mm NL Pure and many other binoculars that I enjoy very much.
As others have already said, an SF, SFL, Noctivid, or NL Pure would likely offer a lifetime of contented viewing pleasure. An important point to remember is there is no such thing as the “perfect binocular,” they are all a compromise of features, components and function to varying degrees.