I agree that the Foka 5 is a very nice glider to fly.
Also that there is scope for mis-rigging - see
Air Accidents Investigation: SZD-24-4A Foka 4, G-DBZZ
however having said that, the Foka/Cobra series gliders have been rigged thousands of times without problems. The Bicester incident happened as a result of people rigging the glider without having had the proper training and experience. Never a good idea when rigging any glider.