Well, the way the "equation" worked in my head was this:
Total Commander: starts out limited in functionality and you wonder "what's so special?", but then you find out there are many, many plugins that can do almost anything you want.
Result: If you are willing to customize, it can be "the best".
Xplorer2 (or XYplorer, or others): starts out ready-to-use with lots of built-in functions (that TC may require a plugin for), but less expandable.
Result: If you don't like having to customize and/or the default configuration "out of the box" is good for you, this is a faster, easier approach than TC.
You could replace TC and Xplorer2 in those sentences above with Firefox and Opera respectively, and it would make perfect sense to me. Now mind you I haven't tried TC yet, so I don't know just how limited it may be in default configuration. I feel Firefox is pretty limited without extensions though. Also Opera is demonstrably faster than FF, but I don't know if TC is slower than Xplorer2.