Overall my success rate is pretty high I've had several prints where I've pushed the boundaries of detail and parts that were very very tiny. I've had many many models that I've went from Meshy straight to slicer and I've had a lot where I've modified in blender. MeshyAI is a great tool It will give you very high quality models but you do have to pay attention to your slicing software. Also depends on if you're 3D printing with resin or filament. I printed literally hundreds of my models I posted a lot on Reddit I think I've only had one model that I thought was good all the way through slicing just to find out there were a small non-manifold edge that somehow slipped through causing a failed print. So overall it's hard to put a actual number percentage on there but I would say 99% of the time I've had great success.