I am seriously considering purchasing one of these pneumatic airguns. I have had a gamo for a few years now and despise the pos. The Benjamins seem to universally get good reviews. I had a childhood friend that had one and I remember being so envious. My question is what caliber is suggested? .177, .20, or .22?
I'll use it to shoot pest squirrels in my urban back yard and plink out to about 25m.

The benjamin is a solid airgun for the price.

The .177 will shoot flatter, the .22 will hit harder, I haven't shot my airguns in a while but generally .20 has offered fewer pellet choices than .177 or .22.

Think of the .177 as 5.56, the .22 as .308 and the .20 as the 6.8 SPC more or less.

A .177 will humanely take down squirrels, rodents, etc. but for things like skunk, racoon and the like a .22 is an improvement but a .25 would be even better.

I shoot .177 in all my guns just because it's familiar to me and I don't shoot anything bigger than a squirrel with it.

Awesome analogy, thanks for the reply.

at the factory recommended full scharge of 8 pumps, the 39x guns will have some bark. Not exactly backyard friendly, depending on your neighbors and back yards

That is true, it does announce itself. The Beeman R7 might be a tad more backyard friendly or a Benjamin Marauder tuned down to 700fps or so would probably get you near 80 good shots between refills and be mouse fart quiet.

A little update. I got a Steroid 392 from Tim Mcmurray at mac 1 airguns and I love this gun. Fully pumped it is loud but shooting at 6-7 pumps is fine. I've been shooting the s--t out of this thing. Personally, I prefer the pneumatic to a springer but someone who doesn't want to pump should take that into consideration. Stupid accurate.

ALWAYS remember to keep one pump in these to keep seals closed..also NEVER use anything but airgun oil to lube these guns..WD40 WILL eat the seals!! Transmission fluid works great! Just my 2 cents.....