This is an interesting YouTube channel that discusses free plugins or plugins that you can temporarily get for free (Black Friday, promotions, etc). The author tests plugins in-depth and uses either Gig Performer or Reaper to test them.
For example, see these videos:
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All videos from the channel → Youtube.
I like that he includes how is the sound like A/B (with and without the plugin), he monitors latency and performance and gives useful tips of advice.
A nice channel.