This is a no brainer.
It's your room and your ears. Keep solo vocals focused in the center. The speakers disappear. You'll find you can do this with either configuration. Then you have to decide if tweeters on the inside fit your taste for a more "intimate" soundstage. Most go for a wide and deep soundstage but your preferences in music genre are what matters most.
Speaker placement/room acoustics is at least 50% of this whole gig. IMHO
It's your room and your ears. Keep solo vocals focused in the center. The speakers disappear. You'll find you can do this with either configuration. Then you have to decide if tweeters on the inside fit your taste for a more "intimate" soundstage. Most go for a wide and deep soundstage but your preferences in music genre are what matters most.
Speaker placement/room acoustics is at least 50% of this whole gig. IMHO