IAE make all kinds of panels, shedding gates etc. There will be downloadable catalogues on their website, I'm sure. The outside pens and races on the moorland farm were IAE, I think, and were slick, light, strong and easy to use.
Sorry to hear about your disappointing experience with Bateman, farmershort. My own experiences with Bateman have been excellent. We chose them for the cattle handling facilities at ex-BH's farm, and were delighted with the products and all aspects of the service.
I have also had great customer service from Ritchie. We had them make a slight adaptation to a lamb weigh crate. It was a great piece of kit.
One thing to think about is how specific the connections are. Some systems, e.g. Alligator, are very specific. The only way to attach other, non-Alligator elements to the system is with baler twine :/. Whereas the IAE stuff I've had used a simpler, more open pole and loop system, which other, non-IAE elements were more likely to be able to hook into. (Although we did use baler twine quite a bit, too, of course.
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