We've noticed poor quality as well with older Quadro hardware.
However, CPU driven renderers such as the built in Cinerender work fine on our older workstation hardware and benefit a lot from the multicore Xeon processors. I would imagine it is the same for your AMD Ryzen CPU.
I have a feeling (so not based on hard facts!) that using Twinmotion going forward, you'll have more hardware upgrades that are needed, to keep using it optimally over the years. So besides the future investment of Twinmotion (it will not be free forever to use the latest version), that is another thing to consider.
Erwin Edel, Project Lead, Leloup Architecten
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