Your question suggests that you have no basis for evaluating the quality of a speaker. The only thing I can assure you of you don't measure it by its cost, size or type. Design and quality of parts/built are very important but they don't make a speaker "great" either.
If I were to assume that you already had the best electronis and sources, then I would say the speaker that is "best" is the one that sounds best to you in your room. That is YOUR great speaker. But if you don't have the best room, or the best components, that same speaker may produce sounds that lead you to believe it is a POS or some such negative evaluation, but another speaker may work just fine with the same stuff (this indicates a probable mismatch between the speaker and you room and/or electronics.
It's really about your room, your expectations, your finances.
If I were to assume that you already had the best electronis and sources, then I would say the speaker that is "best" is the one that sounds best to you in your room. That is YOUR great speaker. But if you don't have the best room, or the best components, that same speaker may produce sounds that lead you to believe it is a POS or some such negative evaluation, but another speaker may work just fine with the same stuff (this indicates a probable mismatch between the speaker and you room and/or electronics.
It's really about your room, your expectations, your finances.