When looking at BB, check to see if they have bracing from front frame to rear of box running about 1/3 distance from each side. These bars will keep your box from bowing and add some stability. Also look at the 3 PH frame to see how strong it is built and how it is braced to the back of the scraper. The more substantial the better. I saw one on TBN post the other day that just had the 3 PH mounted to the front scarifier bar with just a vertical riser with no bracing what ever to the back. This is not a good idea if you want it to stay in one piece. That design is just waiting for the main frame to twist and bend.