The best evening I ever had with mine (591) was 9 kills. It was the first hunt of the summer, on what I called the truck stop ridge. Strip farming was the norm, and I knew the area well. I would ease along and glass, kind of like a mailman walking a route. I had certain spots where I would sit and watch for a bit too. Had fashioned a set of shooting sticks for shooting from a seated position, but most that afternoon were shot off hand. Seems like I recall that several were small pigs of the year, and one picked off a low limb.
I have read that the trigger can be improved on the 591/2 series, there may be an aftermarket that can be used. I have also read that a rear action screw added to the rifle will improve accuracy. But mine has always shot really well. And other than exploring some type of mild trigger improvement on mine, I will not modify it further. I went through an extractor, weakened it by storing the rifle with the action closed, my take on it anyhow. The longish arm is tensioned when the bolt is closed, and the fix was a new extractor. Did 5-6 years after purchase. I since store the rifle with the bolt open.
The cartridge was ahead of the .22 mag in velocity, and no doubt flatter shooting. Had some other makers got on board, and somebody chambered a slightly higher quality (read better features) rifle (better trigger and bedding set up, slightly heavier tube) something like what Savage has done with its different models, the 5mm would have done much better commercially. I think so anyhow.