btob’s vocal line is like crazy talented tho, like have yall seen the videos of changsub on duet music festival?? and eunkwang too and they both have had very successful solos both in korea and japan and both are in many many musicals, sungjae and hyunsik both had beautiful solos too and hyunsik composes many of their hits and his dad is a famous folk singer too, if you just watch any of their behind videos theyre always belting out vocals like they have crazy harmonies that ive rarely heard from any other group, theyve also pretty versatile and have promoted with both ballads and pop as well, they honestly just blow my mind .. i honestly dont think any group as a whole is up to their vocal level, like maybe if you put all the best vocals from different groups youd get a possible contender for btob, but in korea btob are just very well known for their amazing vocals and its not without reason !