I'll second what GX said about KoAloha concerts. I've owned 3 and they have all been sound canons. I currently own the two in my avatar -- one gloss "skunk" and one pikake. If you want loud, then you want a KoAloha concert. They make great strumming ukes, but the string spacing is closer than other ukes so they're not the best for fingerstyle (although they're not bad for it), especially if you have large fingers. Also, in general the pikake (matte finish) KoAlohas do not have as good of sustain as the gloss finish ones.
I also own a G-string concert and mine is not nearly as loud as my KoAlohas. It has a very nice refined tone, but just not the volume. It's the only one I've ever played though, so maybe I got a soft one. The G-string on the FMM (about half way down the page) is actually a super price IMO. Compare at MGM's new price. The wood's not the prettiest I've seen though... My G-string's fingerboard plays great, with plenty of room.
That's my 2¢.