It is very rarely you come across a plugin that can be called a game changer. This is exactly what happened to me after i tried AI MASTER by Exonic UK. I must admit that at first I was quite skeptical. Another plugin that does mastering and has only two modes - Analyse and Master.
I am not a professional but I have considerable experience in mixing and mastering my own music. So after quite a few tests on my mixes the results pretty much blew my mind! This plugin analyzes your mix and automatically takes care of everything you need for a great mastering - loudness, stereo image, eq, etc. Sound just a little to good to be true, but it works.
There are no presets or mastering style options. Each mix gets its own private treatment according to its analysis. All you have to do is to play your track on your DAW (you have to keep the right mix level) while the plugin is in ANALYSE mode. Once the track ends just click MASTER and than the magic happens.
I think 69£ is not a negligible amount, but it's pretty ridiculous for having your own private mastering engineer in your studio.