When I first got the Axe-Fx I thought tone matching some of my favorite players was a blast, but you're right: matching it CD quality or YouTube quality recordings leaves a lot to be desired. My experience is the same as Moke. You can get close, get the vibe, but I have found it much more rewarding to take the time to try and match the sound through the use of the amp models, cabs, and parameter tweaking. Not only can you nail pretty much any tone that way, but you get the full rich, almost 3-D sound that I find difficult to achieve with Tone Matching. Even tone matching to a .wav doesn't yield the results as well as just building a patch, at least to my ears. I have also had decent results mixing tone matching with Cabs, but I think that defeats the purpose of the TM block.
Now, what I do think is pretty rad, is the ability of the Axe-Fx to match an amp. I need to get better equipment to do it, but, I've seen some damn good results using the live matching feature. When you match to a recording it only matches 1024 data points IIRC, and with the live amp matching, I think it's 8092 data points. Hence, why the results are so much better. If I'm wrong on this, I'm sure someone will correct me.
The last amp match I did turned out okay, but I think I could improve the way I did it a lot, so I will be trying again when I have better equipment to do it with. You can also amp match a whole setup; so if you have a particular amp with a particular pedal that you like, you can amp match the whole signal chain, not just the amp.