Product review (4 stars): I can't tell you which is better. What I CAN tell you is it tastes ...
I searched for a replacement to the name brand because the last 2 name-brand filters I got made the flow of the water really slow. To a trickle, really. After I replaced the name brand filter with the bypass, the flow was vigorous and strong, again. So, it appeared to be a problem with the filter (plus, I didn't want to take the tubes apart or hire a plumber the check it).

After researching on Amazon, different forums, and talking to some friends, I decided to try the Water Sentinel filter. It's certainly a less expensive option than the name brand filter. It appears to perform as well as the name brand filter does (when the name brand filter performs well). Though without doing full fledged water analysis on the water, I can't tell you which is better. What I CAN tell you is it tastes the same as when using the name-brand filter.

My only complaint, and this may be specific to the individual filter I received, is that this filter emits an audible high-pitched whine as I'm having water dispensed out of the refrigerator door.