If you only want the one prebaked sound... but what if I told you, you could carry one cab around and get the sound of a 1x10, 1x12, 2x12, 3x12, 4x12, 2x10, 1x15, 4x10, 8x10... etc
You may only want one sound - but what about that guitarist who wants to go from a little Fender Deluxe to a Marshall stack... How about if you wanted a little Ampeg B15... and then a SVT 8x10... and you achieve it with just one cab?
It's not for everybody - but opens up a lot of options to you in a portable package.