Well my problem with id3 is it's limited to 30 characters per artist/title/whatever. I know i could use id3v2, but I absolutely hate id3v2. I can zip through my entire mp3 collection with id3v1 or filenames in about 5 seconds, but it takes over 15 minutes with id3v2. Being able to store the id3 tag anywhere in the file, while noble, is a pretty lame way of doing it. Sure it has it's uses, but i would have prefered something similar to tiff, where it stores an offset to the first tag in the mp3 header. That tag then contains an offset to the next tag, etc. This way you could seek right through the file looking at the tags without having to care about the actual mp3 data.

As for using mp3tag studio and tag and rename:
I could not get mp3ts to run on my computer. i guess it's a bug, but the window kept 'jittering' (best I could describe it). i'm almost certain it has to do with the advertisements, because it works until the ad loads.
Tag & Rename is pretty powerful, but I don't like the user interface at all. I also have some crazy little nuances in my filenaming that would be difficult (though probably not impossible) to explain to T&R.