I have owned both, the adhesive ones usually cost less than the channel type and you only have one shot at aligning them correctly during the install. The adhesive used on the product I purchased set-up immediately, so that being said you need to take more caution because your applying this product to a painted surface. Also after about 5 years the adhesive dried out in some places and the vent started coming loose. Once that happens things can get ugly.
The channel type in my opinion looks much better and WeatherTech (Click on link below) makes the best on the market; however, they are not cheap. Fairly easy to install and since they fit in the track no adhesive is required. The only negative is someone could steal them if they are familiar with the product application since no tools are required.
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