I know you put quotes around acquired, so I won't flame you for "testing" these plug-ins before you legally 'acquire' them...

The ones that I use are Neat Image, the KPT series, the and Nik plugins. The others I have no idea about. That's a whole bunch of software that IMHO isn't needed, but then again it depends on what you are doing. If they fit the bill, go for it.
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Just remember that if the company goes out of business because of lack of sales, your software is at a dead end. Support software development and buy what you use.
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