Speaking for the core rigid body solver: we use UE5 with Chaos on Fortnite and all other internal projects, and have been working closely with some larger developers who are using Chaos, so we know it is possible to ship a quality product with it. We are aware there are issues that we need to address though, and if your project is impacted by any of them it can be frustrating. Fwiw, I was on the other side of the Epic/Developer relationship when UE4.0 was released so I really have been there.
On the plus side, Chaos works very will in many circumstances and we’re continuously improving it in terms of behaviour and performance (5.1 will see significant gains in both). So in general I would say we’re happy with the direction we’re going and the progress we’re making. Chaos is our only physics system going forward and we’re working extremely hard to make the best solution for everyone.
There’s still a lot to do, but if there are specific issues we need to address please let us know via a UDN post.