Assuming the doubling of effective power per every 3db sensitivity increase (assuming both sensitivity and power are measured correctly), 5 watts at 107db is the same as 320 watts at 89db. For most 89db sensitive speakers, 320 watts would be considered fine and another 20% (5 to 6) would probably enough overhead.
I don't see a problem with 5 watts...
I don't see a problem with 5 watts...