It's most critical to have front L-C-R matched, so, typically, you would want the same brand/model all the way across to assure optimum voice-matching (use of equal tweeters, etc.,...).
So I would decide whether you want to use a Boston Acoustics CR center based on replacing your Sony fronts with Boston Acoustic front speakers later.
Otherwise, I would just go with the matching Sony center speaker.
So I would decide whether you want to use a Boston Acoustics CR center based on replacing your Sony fronts with Boston Acoustic front speakers later.
Otherwise, I would just go with the matching Sony center speaker.