I really like his voice, but I don't understand why he keeps insisting with the Koffi's style instead of finding his own.

Doudou has stated on numerous occasions that Koffi is his idol, which is he always tries to emulate Tcha tcho in his singing and compositions.

He's even done a few Doudou chante Koffi concerts.

Yes, but I found him annoying after a while, not for the fact he imitates Koffi, but because he never changes his way of singing since he was in Extra Musica has always performed that Tcha Tcho style of looking to emulate Koffi in V12 on the first part of rumba for going with again a faster Tcha Tcho on the second part