I went down this rabbit hole myself. Mostly for V30s. But, there is quite a big difference in my experience. I have/had both 8ohm and 16ohm of both Mesa and Marshall versions in different cabs. I have also have/had vintage(1982) G12-65s and DV77s. The 16ohm speakers all tend to be tighter and have a very pronounced upper mid range with the exception of the DV77. The DV77s are kind of an anomaly. They have a scooped upper midrange. So, being 16ohm kind of suites them well. The vintage G12-65s have a very pronounced upper midrange, but unlike the 16ohm V30 speakers they aren't harsh at all. I no longer own any 16ohm Mesa V30s because they were just too harsh for me. In the room they sounded fine, just not mic'd up. Putting the 16ohm speakers in 4x12s does seem to tame them a bit, but the 8ohm speakers all sound much more balanced in my opinion. The only cab with 16ohm speakers that I have kept around is a Marshall 4x12 loaded with Marshall V30s and DV77s.
