I don't have one and I don't want one but last year I saw a video of a guy in the States who had to send his gun back after a week as the bolt and the probe had come loose and had damaged the barrel. After he got it back with a test card showing all was ok he found out that the gun had no accuracy . He traced the problem to the magazine, it wouldn't line up properly . He used a Benjamin Crosman single loader as it seemd to fit and the accuracy was back.
I have also seen a video of a guy with both a wild cat and an impact and both barrels are bad. The ST rifling is not really smooth but rough with pitting in the lands making the pellets fly in a spiral pattern.
Last week I was at AIR and the chap next to me was shooting an impact from the bench with a bipod. I didn't look at his card but from his moaning and groaning it was clear that the gun wasn't performing as it should have been.
I am sure that there are good ones out there but as with the bad batch of barrels from Weirauch a while back, the importer has to take charge if lasting damage to the reputation of the FX guns is to be avoided.
From time to time things do go wrong with mass produced rifles but it is the back up and the support quality that matters at the end.
A.G