For what it is worth I feel compelled to offer my own 2 cents worth.
Welds on light gauge tubing are some of the toughest to do short of TIG welding. Which would add significant expense. I am constantly trying to build a better mousetrap and the sticking point is always weight vs durability. The Trainrites are a very good balance of strength vs weight. You have to take care of them. If you abuse them yes you could have a problem. But the welds are the least of my concerns. The pouches and rings are a problem. But these are both third party parts and Trainrite does not have direct control of these. I personally have other items I would improve on....but I'll reserve my comments(not criticism) directly for John and Warren. Our club recently bought 5 of the pro model. I built 5 more of my own design(and I had to take great care in welding), in time and material I spent as much or more on the ones from our fab shop.
IMHO for club use and throwing flyers (with the exception of mine)they are hands down the best out there.
Regarding the releases, They are only thing I am aware of, that are commercially available, but they are exceptional in workmanship and reliability. I don't think you can even buy the old style kick releases.