I'd disagree with the above, not because it's wrong but because we all want different things from our shooting.
The Umarex guns are no doubt well made, slightly more powerful (though it translates into very little useful power, you will be luck to break 3FPE) and accurate over a bb gun but they are not as good as a dedicated pellet pistol in terms of power or accuracy. In terms of fun they are nowhere near as good as a blowback BB pistol and a lot more expensive.
If you want accuracy and power get yourself a dedicated single shot pellet shooting pistol. If you want fun action shooting or a decent replica then get yourself a blowback bb automatic. If you're in the middle get yourself a Umarex.
I would have a lot more time for the Umarex pistols if they were better at what they did. If they had used the mechanism for revolver type air pistols I'd have no issue with them. Dressing them up as real automatics and sticking a load of moulded on controls makes them a bit of a enigma. Umarex should have set out to make a great airgun that was a great replica, instead they ended up making a mediocre gun that is a rubbish replica.
I know people enjoy shooting them but for me if you are shooting tin cans in the back yard, a classic blowback BB pistol and a big pile of magazines will give you hours more entertainment. I have loads of them, some of them over a decade old and only 2 have given me trouble, my PPK/S (whose frame snapped after years of service and tens of thousands of BBs) and my Peacemaker which works perfectly but has an annoying wobbly barrel!
But each to their own, try everything and see what you like.
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