BOAC,
The F-7P has a Martin Baker 0/0 seat. The PAF was very good about insisting on Martin Baker seats for all its aircraft including the Mig-19. The ejection seats for the MiG-21 depended on the mark but here is a quote from an article
"4) The CK ejection seat, one of the best for high speed high altitude ejection simply was not good enough for low level by modern standards. One of the clever features of the CK seat was that as the seat left the cockpit the canopy- which was hinged to the front of the windshield in the FL - attached itself to the top of the ejection seat and rotated itself until it covered the entire front of the ejection seat- thus giving unparalled blast protection when ejecting at supersonic speed. I remember a Martin Baker engineer getting very interested in how the thing worked. I had seen the seat but he had not! Unfortunately I was not able to help him. The semi -encapsulation feature delayed ejection in that it took too long to get rid of the canopy after clearing the aircraft and this delayed clear release and deployment of the Parachute. The 300 kmph, 100 meters minimum parameters meant that many low level ejections were unsuccessful."
MiG-21 Accidents - Prodyut M Das
So IAF MiG-21 pilots were told to eject rather than stay in the airplane if the engine so much as burped on takeoff. Probably SOP for all MiG-21 pilots.
The 0/90 thing may indeed be duff gen. I just got back from a Gnat reunion, and the Ajeet had a 0/90 seat which floated to the top of my already weakened brain!
Worf