AVI vs MP4

[PC GAMER]

What are the main "internal" differences of Action! and these two popular formats? That is, which is "better" and why to use with Action?

Further, if selecting MP4, the Hardware acceleration part becomes selectable and offers; NVIDIA NVENC, NVIDIA NVENC HEVC & NVIDIA NVENC HDR10 as possible options, defaulting with; NVIDIA NVENC. What are the differences between them and why/when should we select one or the other?

[Plamper]

What I know is that AVI gives you a flawless outcome with extremely big size(e.g. 30 GB for a 15 minutes video), in comparison the size of MP4 is controllable according to the final piece quality which you can change in the setting, the quality would not be flawless but still great, which I pretty recommend if you want to record constantly. And Action is convenient for new comers, just need to press F9 and off we go.
For the Hardware acceleration there is an alternative choice in OBS Studio(another recording tool) called x264, I was heard from an experienced user saying that if you choose x264 you would let the CPU doing the recording job and if you choose NVENC you would let the Graphic Card doing the recording job, since Action only have three NVENC options, I presume it is about how 'HARD' are you going to push your graphic card to generate your record.
Well my opinion is never authoritative, please do some other researches before you believe some of the theories are true.

[PC GAMER]

Originally posted by Plamper:

What I know is that AVI gives you a flawless outcome with extremely big size(e.g. 30 GB for a 15 minutes video), in comparison the size of MP4 is controllable according to the final piece quality which you can change in the setting, the quality would not be flawless but still great, which I pretty recommend if you want to record constantly. And Action is convenient for new comers, just need to press F9 and off we go.
For the Hardware acceleration there is an alternative choice in OBS Studio(another recording tool) called x264, I was heard from an experienced user saying that if you choose x264 you would let the CPU doing the recording job and if you choose NVENC you would let the Graphic Card doing the recording job, since Action only have three NVENC options, I presume it is about how 'HARD' are you going to push your graphic card to generate your record.
Well my opinion is never authoritative, please do some other researches before you believe some of the theories are true.

Yes, I kind of know what is what, but that is exactly why I want official answers from, you know, the people who actually make this software. They would know for sure, the small details I am seeking. I have now switched to MP4 (for the smaller file size) and I can not tell the difference. I decided to use the NVIDIA NVENC HDR10 codec, since I assume from the three available, it's the "best" one. So whilst the names and ordering make it relatively obvious what is what, it is exactly because of that I would like official clarification.

Notice that now they seem to hate me and are totally ignoring me. I made them realize they can "do" things with Direct X 12 and Windows 7 back in December 2020, and they promised a fix. Since then they did release two updates, re-promised the Cyberpunk fix and still nothing in March. In fact they have not replied in the thread since. The software is a good replacement for me, from FRAPS, but the developers attitude is, now, concerning. They started off well.

[PC GAMER]

Over two weeks and no official reply, yet they answered other threads since, so they are here and reading things. Pathetic!

New release too, which mentions "Improved AVI recording performance" via the patch notes. Okay, good, but I would like to know what exactly that does. In order for them to write that, there must have been something very specific that got fixed/enhanced. What was it?