Thanks for the input. My truck is a diesel, by the way. The fiver is a Keystone Avalanche bunkhouse. I've done the weight calculations, and I don't plan on taking THAT many tools. I have a simple set of hand tools, some general repair tools, a Craftsman "Bolt-on" with the various attachments, and a saws-all. All in all, about 180lbs of tools. I want the bed toolbox for keeping everything in one place (jumper cables, entrenching tool, tow strap, gloves, etc...) and out of the cab. Therefor, I don't mind spending more for a nice secure, waterproof box. I like the Dee Zee 60" flush mount box I looked at the other day. I also like the quality and PRICE of the Better Built model (they're basically the same, just branded different). Again, thank you all for your input, I will take all into consideration.
-Chad