Bought a Pro Chucker 7 this year because I use RCBS for almost everything else. After breaking an indexing arm and going through a lot of adjustment, I've gotten it to work well except for the primer feed system. I oft have problems with the small primers not wanting the feed arm to push the primer forward, so sometimes I have to assist it manually, and have had issues with the large primer arm affecting the proper indexing of the plate. When I loaded a bunch of cases I already had primed, and forwent the primer feed, the system works wonderfully without any complaints or flaws.
But the primer system is a problem, and other customers I've read about have the same exact complaint. In fact, when I got my extra indexing arm after I broke the original trying to get the whole thing to work, they sent extra primer feed plates that I didn't ask for, because they sheer off one of the tabs. The press works well besides that one station, its THE problem. Turns out my indexing troubles were from that as well.
All in all, I don't return stuff unless its broken, sell anything under almost any circumstance, so instead I've learned how to adjust the press, and adjust my method to the press, and it works for me now. I progressively load lead bullets exclusively, so it turns out I didn't need the 7 stages, but it also means I hand place bullets and gotten into a rythme where if the primer arm fails to feed or affects the index, I quickly hand adjust and keep going. I use the extra empty slots for inspection, and realize I could have gone way cheaper, but that's in the past.
Positive notes is that it is very solid and can handle a full head of dies without trouble when the primer feed isn't giving you trouble. Measures of Bullseye have come out extremely consistent and the powder feed works very well, and did i mention that the whole thing works very well except for the damned primer feed?
I gave it a 1 star rating on Amazon, and when I started, I too felt like taking it and chucking it into the river. I came on this forum and swore I'd never buy RCBS again. To be honest, I'm still mad at RCBS over this whole deal. But, I've gone back to their products and now that cursed ProChucker is now a valuable part of my handgun reloading setup. My experience.