@nomadic Sorry I did not see this forum topic until after your purchase to respond prior. I have an MSI Gaming Laptop that I bought in 2013 (GT60 20D) that I am still using.
It is very old now, but still runs exceptionally well and can still play most if not all modern games if graphics turned down some. It has been a very good machine and it now lives in my workshop when I need to look something up that I am working on or listen to music when I am in there. The power brick is huge as you mention and the fans are a little loud when the graphics card is running hard.
The keyboard is a little messed up now as it has had a lot of use and the only "major" problem I have had is that the bios has started to flake on it, so I try to not reboot it if not necessary. I would recommend turning off any MSI splash screen on boot if there is one, because I can not see when I have issues and because of bios issue I mentioned, I can not get it to boot to the bios screen to edit it now.
If your new machine is anything like mine I think you will enjoy for a long time!