I like Amplitube...mostly my sounds are going to be more cleanish OD tones...Bassman, OD'd Deluxe, Plexi kinds of sounds. It doesn't do very well on heavier tones, but...
Guitar RIg and that Legends thing were just rotten for the kinds of sound I use. People say the heavy stuff is better, but frankly, if it doesn't have the meat and potatoes sounds--well, I didn't explore further. All I know, is there is nothing you can pull out of NI's "Twin" amp that sounds anything like a decent Twin reverb. Not even resembling it. People seem to like it's recto amp sim, but I don't like real Mesas, so...again, I didn't do too much playing with it during the demo period.
Now, I did find a lot to like in Line6's Guitar Port, but, it can be flaky routing to record within an app, and there's not a very wide variety of "good" there.
If I HAVE to DI heavier stuff, I've got a little box that can be stellar---
www.v-stack.com --little analog stomp box, peels back the distortion with the guitar's vol knob, and it very pick sensitive. You can actually get it where it clean picking lightly, and screams when you dig in. Pricey for effectively a one trick pony DI...but, it kills the plugs and PODs and JStations, etc I've used. Works well as a dist pedal in front of a clean amp, too.
All in all...I'd rather use SansAmps and V-Stacks, etc--analog pedals through my old ADA cabinet sim than any of the digital wizz bangs. But, Amplitube has gotten me where I was going morethan a time or two.