That being said; I don't think that there is such a thing as a decent portable combo. Any combo I have ever seen or used, if it has enough power to gig with, you need two men and a boy to carry it. Someday there will be soon, one thats lite enough, but as of yet I don't think you'll find one. One 15" inch cab and a small head, still is the best combo going IMHO.
Depends on what everyone means by "portable" The OP is asking for something that is really on the edge of practicality.
A small enough combo to rehearse, small gig with, and take on a bus or train? Doesn't seem like such a big deal until you add in the drummer.
My GK 1001RBII 115 is heavy yes, but it has built in wheels and a tow handle. I drive it everywhere. For me, I think it is very portable for what it is capable of. And it's capable of a great deal. Except riding on a bus. Maybe towed behind?
JKT