On the flip side i would trust this engine to get me back safely, I have seen the RB211-524 with 2 blades missing from the stage 5 IP knocked off by a faulty check valve that clattered right down the rest of the compressor.
After extensive mapping and consultation with Rolls, we ran the engine at 1.6 EPR (power assurance/Vib check) with a tarmac temp 40 degree heat and we really nailed this poor engine.
Results @ 40degrees, 8% EGT margin and a broadband Vib of 2.3 MAX.
What a fantastic engine and a testament to a great company.
It got one flight home for immediate change.