Archer Airguns started selling the XS46U some months ago.
I'd say that this is an attractive air rifle at a good price. The finish is good and it's a nice gun for plinking. It's clearly based on the Shanghai Airguns QB36-2 model, although that's not clear from the outside. There are some photos of this at http://www.archerairguns.info/search?q=XS46U
On the downside, most examples give a pretty good "twang" when fired. I could live with that if the muzzle velocity was OK: but unfortunately that's somewhat of a problem. This is why we have stopped selling the XS46U at the current time.
Before accepting the product for sale, we tested some in .177 caliber and found muzzle velocities of around 810fps with 8.6 grain pellets. This is, of course, some way below the 1,000fps specification claimed by the manufacturers but we provided this information in our store so that customers could make their own decision.
However, some customers provided feedback that muzzle velocity was not up even to that level. As a result, we tested EVERY GUN in our inventory. Here's the results:
.177 cal. Factory spec 1,000 fps. Actual tested performance with 8.6 grain domed pellets averaged 744 fps. That's 256 fps below the manufacturer's claims - 26% slow.
.22 cal. Factory spec 820 fps. Actual tested performance with 13.9 grain domed pellets averaged 664 fps. That's 156 fps below the manufacturer's claims - 19% slow.
Obviously we've fed this information back to Xisico!
So do the guns shoot too slow, or is the manufacturer's specification just too high? As the consistency of muzzle velocity between individual guns was good, I'd say that the manufacturer's specification simply needs to indicate the type and weight of pellet that the guns were tested with to achieve the claimed muzzle velocities.
I'm sure the muzzle velocity specification can be met with very light (lead free?) pellets, but unfortunately this is not the case for the medium weight lead pellets that most of us shoot. As Xisico's specs don't give that information, customers assume that the claimed muzzle velocity (or something like it) can be met with "average" pellets. Unfortunately it can't.
Archer Airguns Inc.
Online stores http://www.archerairguns.com