I own one and they can be turned into a good air rifle with a little work . The old addage for air rifles is .177 for paper and pest birds, .22 for fur bearing small game.
It is an accurate gun but Gamo triggers pretty much suck. There are a couple of aftermarket triggers made . I got one from an air rifle forum called Gateway to airguns. There is a huge amount of air rifle know how on that site. I was able to tune my Whisper into a fantastic little rifle. They are not all that quiet though , and DO NOT use those crap raptor pellets that they try to sell to get supersonic velocities with . The internals will wear much faster and have been known to break springs. They are also not all that accurate. In .177 if you use a standard lead pellet that shoots well, you do not have to worry about hitting 1200fps . It is still a 12+ft=lb rifle and will effectively (and humanely) take squirrels out to 30 yards. There are those who have taken them at longer ranges but 30 is my self imposed limit . I don't care for wounded critters.
I would suggest a visit to the GTA website and do a look around there before you buy . It doesn't matter anyway , if you get bit by airgunning it won't be the last gun you buy LOL .....
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