@Kurumi-Tokisaki The best in slot is the one that maximize YOUR playstyle, not the playstyle of a party that want you to do what they do. There are so many different classes and some of them use different styles of fighting, so that weapon or set may not be the best for that person. BiS is just Preference and opinion. True that a lot of the best have a lot of stats that does help but might not be the stats and stuff that someone wants and or is looking for. It's like twin daggers, people don't like them because they hit for less but if they they're actually fun and for comboing. People can say what they want but it's what fits that individual that should matter, not what someone else tells you to do. "Don't play this because this, don't use that because of that, listen to me and you'll be God." what if it doesn't work for them?
I agree since I played Double Saber back in the JP days where people said it was horrible and this post reflects exactly how I felt and feel now.