Did some web searching and apparently the missing boxes were a pulse doppler MAWS according to chinese-military-aviation.blogspot.com. Perhaps eliminated to save weight since the production aircraft use less powerful engines than the first prototypes.
Excellent is a relative term. I'd like to see a maneuvering Z-10 with a full spread of 16 loaded HJ-10s, which up till now I have never seen.38 PLA army aviation recently conducted training of armed Z-10 demonstrating excellent low-attitude manoeuvrability....
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