The most immediate difference you'll see between BAK and TonnoPro truck bed covers is the price. As a quick example, the cheapest TonnoPro hard folding tonneau cover starts at $549.99 whereas the cheapest BAKFlip starts at $800. That's a $250 difference, which is nothing to laugh at.
However there are some key differences between the two brands.
First, the BAKFlip truck bed covers give you full truck bed access. This is a necessity for some people, and can be worth the extra price if that's what you require.
Second, the BAKFlip truck bed covers have a more flush look and a more premium feel, which makes them overall a more premium option.
If you just need to get the job done and want to save some money, we recommend the TonnoPro line. This is still a high quality option, it just doesn't have some of the premium functionality and flush look that puts BAK solidly in the premium side.
All TonnoPro truck bed cover orders come with a few extra goodies: a tonneau cover cleaner spray bottle, a tailgate seal, a torch truck bed light (to help you find cargo), and some work gloves.