The X5 frame is very stiff, so any performance benefit would be minimal, even on a track. Even the X5 M doesn't have a strut tower brace.

To answer your question, I don't know of any.

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2017 Nissan GTR Red/black - Tune/midpipe
2013 BMW X5 50i M-sport Alpine white/black - Dinan stage 1
2016 Jaguar F-Type R Gray/red