Soundports change the body resonance often raising it a half step of so this does effect the overall tone IMO. I was told by a very respectable builder that its "washes out" or takes away the tone character of the basses. I Agree with this. They are probably good if you play a lot of chamber music for the other musicians. If you hear yourself better and you think you sound good then this should help a public performance because you are more confident.
But when it comes to beauty of sound not for me. Have played and owned many instruments and have yet to hear a guitar with a soundport that made me say...wow that is a beautiful tone. In fact like peter said I heard one that had the ports by ruck and to me it destroyed the beauty of the sound.
2006 Greg Byers(fan)2009 Eric Monrad(maple) 2018 Simon Ambridge Model 40 Satinwood. 2003 Tacchi Simplcio satinwood 2017 E. Bottelli 52 Hauser, 2002 Jeff Elliott spruce, 2017 Richard Reynoso, spruce/maple, 2015 Herman Hauser III(Cedar)