A very interesting performance comparison from 5.5 to 5.6 i have seen many people report big performance gains mainly due to RHI thread time reduction and possibly better culling ? (primitive is 2 to 3 times lower in 5.6)
It’s also more stable (one stutter completely disappears on 5.6 at 0:29)
Unreal Engine 5 Performance Comparison (5.5 VS 5.6) - Quixel Dark Ruins Sample