I tried Helium and did not like it very much. I have been using Dr. TAG for a long while now.
I just found Helium (I only used it yesterday on about 34 new MP3s I made) to be too buggy or clumsy. I mean, the thing I want most is to set the tags as easily as possible. With Helium, sometimes it picks up the Track # sometimes not. And when I created a template like Track - Title, it kept selecting Artist - Title as the template to use. I figured it had some intelligence and would say "The first item is a number, assume it is a track" and pick the correct template.
Maybe I am just used to Dr. TAG, CTRL-W (Automatic fill), figuring out the filename pattern for me so I do not have to click through each file, set the track, or set the template, etc....
Squid2k1
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18GB of Green Mk II Fury - Fast As A Shark
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Squid2k1
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18GB of revived Green Mk II Fury - Fast As A Shark