It's a nice looking and good sounding plugin. It's transparent so you'll have only a gain boost. The problem that I have with this specific plugin is that I use Logic Pro and I already have a stock gain plugin of 24 db so this one is a duplicate. I was expecting something more precise in terms of step to reach the 24db but it's basically a copycat of Logic's gain plugin.
Vinyl is a good plugin that adds noises to your track. You'll have a lot of option and all the noises generated are really great. It's maybe only my taste but when I use it I feel that all the noises are too much just at 30%. The best use that I do with it is to add noises to emulate vintage instruments or recording. For example, I use it in addition to the B3 Organ and a Leslie rotation speaker to have a 60' gospel organ sound.
I use it with logic pro x 10.4.2 and high sierra. never a crash or a problem.
SPAN is awesome. It has all that you can desire from a spectrum analyzer. All the info, all the analysis, everything you need to have all the data of your song. Put it at last of your master channel and see in real time how your mix/master is going. and it's free.
I use version 3.1 with Logic Pro X 10.4.2 on High Sierra. Never had a problem/crash.
It's a great tube compressor. Same flavour as the Waves CLA-3A but this is free. I've compared the two side by side and I haven't noticed a difference. The possibility to adjust attack and release time is a plus. Highly suggested on vocals and drums. I can't believe it's free.