both have the worst chins ive ever seen but I'd say Chinny Con Khany has the worst chin in british boxing history as hes been dropped and stopped by nobodies and feather fisted guys whereas Christie was getting KO'ed by top fighters like Michael Watson and Mark Kaylor.
Christie's chin let him down at Area Level later in his career when he'd be hanging on after a good shot after a few rounds. Skill-wise he was still the best in Europe (other than maybe Kalambay) right through his career as could be seen in the Eubank sparring fights.
what about Herbie Hides chin, he got knocked out by Vitali without the punch being landed, it is on you tube somewhere, take a look.