Hi,
Auto-marking is quite a dangerous function, since you easily may delete something that wasn't meant to be deleted.
I only use it with everything on 100% equality.
All other stuff gets sorted by hand, but even this works very fast with similarity.
Additionally I always delete to the thrash and check afterwards explicitely that I didn't delete something wrongfully.
I can recommend similarity very much, I easily sorted half a terabyte of duplicates away in only a few hours. I also checked the competition but similarity was the most useful program.
But you definitely need to buy it since only the precise check is the truly trustworthy one. It was a leap of faith for me, but I never regretted it.
Currently I use it for finding duplicates in my photos - works quite well there, too.
And beware: similarity uses up a whole lot of CPU and GPU calculating power with the precise algorithm. It's the only useful program I currently have that actually gets my Workstation to 100% for several hours - an dual octocore xeon (16 cores @ 2,7 GHz) with a GTX 970.
But the results are really good.
To your question with the artist information etc:
Similarity has two different runs, you can either find duplicates or analyze files - the "play" button is a dropdown.
It only get the tags if you do the "analyze" run, too.
Bye,
Gridwolf
