Balder side sword has a very flexible moveset, but Estoc's R1 and dashing R1 is great for fighting those that turtle from my Darkmoon blade buff. BSS can stunlock, but Estoc does more dmg with BSs. BSS suffers less from not being able to buff, but Estoc can be used behind a sheild when I see the need. I just keep switching between these two and regretting it everythime. They both look awesome too.
I tried having them both, but which to buff is still the hardest choice. Besides for the weight I spare I can equip other stuff.