Regarding the prototype VC10 escape system, a chap who worked at Weybridge as an apprentice was on my Aero Eng course. He told me that there was a tape of Trubshaw's struggle with G-ARTA in which he gives the bale out order - followed a little later by "It's OK chaps, I've got her - COME BACK, COME BACK!!".
The RB211 test aircraft also had a crew escape system via the lower freight bay door and I recall being shown it whilst on a visit to Hucknall.