Shopped these a bunch before I did mine with Herculiner.
Here is the basic run down.
1. Duplicolor (least durable, least expensive)
2. Herculiner (In the middle, but still a good deal, search around)
3. Line-X (super durable, most expensive)
Depends on what you plan on doing with the bed of your Bronco. If it is moderate, light use, Duplicolor or Herculiner should be fine.
If you really tear the back up with heavy equipment or loads, go with Line-X.
If checked out all of them in person. Line-X is definetely above and beyond, but because of budget, most of us end up going with 1 or 2. Up to you, but if you do good prep work, I'd say you would be pleased with the Herculiner or the Duplicolor if you aren't abusing the bed.