I use homemade racks for my bp's and they work for me. They are cost effective and I don't pay for shipping. but if you are going to keep it small scale like under 10 snakes you may want to check out animalplastics.com I have one of their economy racks for my geckos. what I like is I can run either 15qt or 28qt in the same rack. it holds either 12 15qts for hatchlings or 6 28qts for breeding trios or any combination of the two sizes. I used it for my hatchling rack until I started getting more that 1 clutch a year. I really like them but I can build 3 41qt 5 high racks and buy t-stats & tubs for the same $$$$
Go with iris tubs they cost a little more but they have flat bottoms. easier to clean and beter contact with your flexwatt so less energy to achieve perfect temps also much heavier duty. but if you are tring to save $$$ my second choice is the sterlite over rubbermaid because they run longer and lower on the dimensions gives the critters more room to sprawl out vs the rubbermaid which tend to be taller.