I am not a fan of the larger SAKs for the same reason John gave.
I do find the little classic on the key-chain handy and usually have the aluminum sided standard model in a pocket.
(I wish it was locking instead of slip, but oh well)

I have owned several versions of the SAKs with multitudes of blades in them and the truth for me is they are too bulky to carry and too awkward to use easily.
I find it easier to just carry a simpler blade and have a small leatherman in my tool kit.

PS, I am not very impressed with the SAK saw blade either. They are too small for serious cutting and I have snapped a few. (YMMV)