garyl43 - Shipping wise, having a 2 part cage is definately the way to go. You wouldn't believe what it costs me to ship a 35 lb package. I'd have to rent a semi-truck just to get an 8 footer anywhere. That would be cool and all, but wouldn't fit into anyone's budget too well. Using our sale pricing on 4 footers, a custom order 8', 2 part cage would be about $500. A 6' about $400. Both prices include shipping. Weight wise, the 8' would be right around 70 lbs.
budgie - The true outside measurements (off the top of my head, and at my office away from cages, notes, and tape measure) is 24 wide, 24 deep, and 17.5 tall. I've been heating mine primarily with heat tape, and have used the old standbys like light bulbs etc. I don't have a RHP to test with, so I don't have any personal info to share. But I can't think of any reason why it would not work, or that it would cause you any problems.
Funny thing. We started building our plastic cages because we needed to replace some wood/melamine 200lb monsters and couldn't find anyone to give our money to. Well, we found the websites, email addresses, and phone numbers, but couldn't get a reply. So we finally found 1 guy that called us back and we ordered a 2' cage to test before we ordered 40 4 footers. Then we waited for about 8 weeks with 0 communication for the 1 cage to show up. For what we paid, the quality was subpar. Then figuring in worst case scenario of 8 weeks x 40 cages = roughly 6.15 years for full delivery. I know that number is unrealistic, but I was irritated
So now we own O2 Plastics LLP., we build cages, ship every week, and the only way we have time to add to our cage collection is through prototypes, scratch & dent's or damaged cages. We have probably the ugliest cage collection anywhere. My personal favorite houses my lavender albino and pied
het ball pythons, and it came off the back of my truck doing 80 on the interstate! I had to fix 1 crack and 1 seam, but other than that and the cosmetics, it works great.