Would updating your slot be good enough for you? It wouldn't work with 4.0 or lower firmware (iirc). If it is, it should be possible to do that update.
It doesn't work below 4.0 as it is. As I said earlier, it straight up crashes now, even when I go back to 2.1.0 firmware through Choi. So, having it work at all would be nice. Since I don't have the option at all to load games below 4.0, I could care less about updating the GC Slot by this point.
So, as you can see, that's why the choice doesn't matter to me. Also, I can see you're new to this thread, but I mentioned earlier I have two Switchs. One for casual use and the other for homebrew. I don't really know what benefit I get from being able to load games games below 4.0, unless a coldboot exploit is discovered. But even then, I don't mind loading up through auto-RCM all the time.
After all, it's as Reggie said, but it can apply to homebrew as well through a bit of rephrasing. "We believe the easiest way for you to load payloads and have a homebrew experience with Atmosphere is with your mobile phone. It's always there, it's always with you." As long as my phone is with me, auto-RCM is the nicest option I got, I can stick on 5.1 and if my GC Slot updates, I can play Ultimate.