They just don't build them like the used to
Read this NTSB report from the mid 70's regarding TWA flight 841. A 727 that fell from flight level 390. The old style flight recorder showed 6g and 470Kts at one point.
I wouldn't want to test that in an Airbus.
http://libraryonline.erau.edu/online...s/AAR81-08.pdf