Things I liked: Bought both the .22 and .177 versions 4 months ago - the .22 is a tack-driver right out of the box with dime or smaller @50 yds (artillery hold) using pellets from 9.7 gr. up to 22 gr. - I like its performance with the 13-14.5 gr range pellets. It needed minimal setup work (Locktited the screws, no other adjustment besides replacing the Gamo 4X scope). Can't say the same for the .177 version: even after restorquing the screws with Locktite, checking and reseating the action in the stock, and replacing the scope it still shoots all over the place - over 3" at only 10 yds, and not much improvement after trying 8 different pellet types, and 4.7gr to 10gr weights. I got down to 1.5" groups from a bench rest with Crosman 7.9 hollow points, but when hand held (artillery hold or hand grip, no difference) I still had 3" groups, but grouped 5" off-center! Shifting the support hand forward or backwards an inch or so just moved the general point of impact around and did not improve groupings.
Things I would have changed: Gamo's 4x scopes on these were very disappointing - I also had scope stability/drift issues after sighting in, even after using Locktite on all the mounting screws. I replaced the Gamo scopes with 1 Leapers Golden Image and 1 BugBusters 3X9 AO scopes - it reduced the eye strain, they seemed to be brighter optically, and I haven't needed to resight or realign either of them. I prefer the thinner mil-dot of the Golden image to the thicker BugBusters mil dot, and might get around to putting it on the .22 tack driver one fo these days! Hello, Gamo: your hi-power gas pistons (and springers) need better scopes - at least 3X9s, and preferably 4X12s for the longer range hunters!
What others should know: After around 500 rounds, the .22 groups are slightly tighter; after around 750 rounds the .177 isn't showing any improvement in group size. I own 2 Beemans and another Gamo (NRA version 1000 fps springer), and they all outshoot this particular .177. ue to bad midwest spring weather, didn't get to seriously shoot these new ones on a measured range until around 2 months after purchase, so I was beyond the Pyramyd 30-day return period so I did not try to contact them to see if this .177 was just a sub-optimal fluke or not. Other than this particular one, I've had very good experiences with my Gamos.