Hard to customize
I thought the idea of being able to customize these to my own specific needs would be great- the next best thing to getting custom-made orthotics.  Turns out, it's not that easy to get the exact right placement and combination of the pads to suit your foot.  You can stack multiple pads to get the height of arch support you want, but for me I could feel the star-step edges of he pads as opposed to a smooth built in arch of a normal insole.  Also, the support you get is more of a "cushioned" support than a "stiff" support.  All I all, these did not give me the support I'm looking for.  I will stick with the pre-formed rigid arch supports.
Rating: 2 stars