I'm a youtuber, have been for a while. Granted, not a very popular one. But Throughout my time of making video's I have tested all sorts of different game recorders, from fraps, dxtory, bandicam and so on. But none of those really hit the spot, yes they gave you a simple recording, but none of them provided any excellence or standed out in some form. Mirillis Action! is by far the greatest game recording software available, you can record in both avi or mp4, depending on how you want your video, quality and how good your computer is. It's tiny file-size makes it easy to store on usb's etc, allowing you to take it anywhere. But by far, the most valuable and greatest thing I have found in Mirillis Action! is the webcam features. Everybody love's to see horror reactions, using facecam's to allow this. But no other software actually has a built in webcam interface that will automatically combine your webcam onto your video, with perfect matched timing and functionality. This is very useful, especially if you're doing horror let's plays, such as myself.
Overall this software is amazing, and pretty cheap too with the functionality you are getting.
However, with great software comes a few problem's, that I'm sure will be fixed, or features that are lacking to be added.
My main problem with this is audio, you are able to do as other softwares alike this would, use two different tracks if you want, you can adjust the ratio of system to mic audio. However, this can be an issue, as you may find some game's have very different audio levels. Because of this, it's very hard to find a ratio balance that provides good audible mic quality over gameplay, whilst ensuring you can hear the gameplay too. If you find the balance, it is perfect. But maybe, and I hope Mirillis do this, but having an auto-balancer, or a testing of somesort would deeply improve with this.
This being said, that is the ONLY problem I have had with this software, and you can get by that very easily, as long as you spend a while configuring it and testing it repeatedly.
This is a purchase worth making if you are into the YouTube community. I would Highly recommend if you are a gaming youtuber, to purchase this as it will open your recording ability to a new level. Plus I haven't even gone into the exporting and auto-uploading choices available in the software. Say's it all really.
So yes, It's good, in fact it's great! Definately worth the investment!