I don't like how the manjaro team does it specifically. A lot of the time i've seen packages break in Manjaro that work fine in Arch, then Manjaro users come into Arch forums acting like its an Arch problem when it isn't.

Also, their driver install helper causes more problems than it solves, which was especially highlighted in the transition to open source official nvidia drivers. Couldn't install the open source ones for the longest time, and couldn't install the right ones from the repo with pacman directly. Caused some major issues for a friend I was helping.

Helped him switch to proper Arch and all the issues went away.

Valve on the other hand puts extreme effort into maintaining stability. I use it regularly and have zero issues, though I use it as-is out of the box.