Hi Lionel
It should be remembered that not all speakers respond in the same way to the test signals used in arriving at sensitivity/efficiency ratings.
It is always best to listen (not always possible of course) to speakers before buying rather than buying solely from paper specs.
One way of doing this is to go round the music stores trying out different amps to get an idea of the "sound" of the different makes of speakers.
You & I might well listen to the same speaker/cab set up & hear different things which makes it harder to go with recomendations from other people about systems that you have not heard for yourself.
Confusing........of course but all the more rewarding when you get it right
One of my "projects" in the pipeline is to be a guitar cab with an "active" cross over system like those found in multi driver hi fi/pa cabs that would have the benefit of being able to be "tuned" to suit the user, wether I can ever get it to work properly ???????????????
Cheers
Dick.