Both products work really well when used as directed. You can see the side by side comparison here:
Packtite vs Bug Oven. With this comparison you can see that the size of each product is different, the material and contruction is idifferent and the warranties on each product is different. The 3-6 hour range is given because the more items or you put in at one time the longer the items would need to remain in the product to reach bedbug killing temps. Please let us know if you have any other questions.