Thoughts on a GAMO Big Cat pellet rifle... What is a used, like new one worth?  Noticed it does not have iron sights, but only an included scope.  Can a sling be easily attached?

If you are looking for a semi-new used one, I have a crosman G1-Extreme with the scope. It is the same FPS as the Gamo Big Cat at apprx 1200. both are break barrel which is great, you save money by not buying CO2 cartridges and save your arm from pumping hundreds of times. No sling can be attach to the Crosman, I don't know about the Gamo. Let me know if your interested

I like my Gamo. It's about a year old and I've had no problems at all.