I'll put in my vote for Animal Plastics. I currently have two of their racks and will be ordering a third in the near-future. Their customer service is top-notch as are their products. Ali is great to deal with and the assembly and craftsmanship of their racks couldn't be better. I only keep ball pythons though and don't have any experience with their cages or larger arboreal racks. I know their lead times can be a while, depending, so if you need it pronto, you might want to make temporary arrangements or look elsewhere if that's an issue.

I've bought from Rich at RBI for various things, primarily for my rat racks. His products, the in-house stuff he's designed as well as the items he stocks, are top-notch as well but I can't attest to his racks. My only hesitation with buying his racks is the size limitation as far as the number of tubs. Not a huge issue but my space is limited and if I can get a 12-slot AP rack for equal to or only slightly more than the number of RBI racks it would take to equal that, wellllll...either way, between those two companies you can't go wrong for quality and customer service.