Opinions are like a§§h0les..........
... ... ... . because everyone has one!!!!
Seriously, you should check the TDR on-line archives including the polls; this has been kicked around before and the feedback you'll get is right on the money. Good luck!
My own 0. 02 cents - find a vendor locally and if their product and after-market service meets your expectations, you're more than halfway there! I went with Linex myself, but it's not just the product, it's the franchised operator and the quality of their work that really counts! Valley Line-X in the greater L. A. area did me proud in early 2000 and I am not unhappy - I actually got them to do not only the bed, but also underneath as well, as we take the truck and camper off-road in severe winter weather conditions (snowboarding).
Oh and did I mention that my nearest Line-X dealer is at least 3,500 miles west from my current location? Warranty issues should be also be a consideration in your final decision.
Take your time, do it right and you'll have no regrets!
Good luck!