Had one myself for a few years in .22 , the .177 version seems to be the rarer of the two. When I came to move it on I got mucked about by a lot of real time wasters Eventually after 8 months I sold her for what I had given for her£500, I didnt loose but I didnt gain on her. A lot of people beleve there the best of all the Airsporters , myself ( having ownded them neatlly all ) beleve it was over -hypded(sounds-familiar) and offerd no real improvements over the standard S models has regards triguer, power / accuracey. I buy my rifles to use not to look at and handle with gloves ., the Centenary was a lot of iceing on a very ordinary sponge cake to my mind. Good luck with any sale.