I have never tried them. I too have flat feet, and was experiencing "heel spurs". Very painful and it prevented me from doing any walking for exercise, forget about jogging. I went to Wal Mart, and they had a Dr. Scholl's display that had a "machine" to test for arch supports. You take your shoes off, and stand on the foot pads on the machine, and after a few moments, it shows the results. At that point it tells you what shoe insert insole it recommends for the best correction. The display has about 20 different insoles, depending on the amount of correction needed. Of course, I needed the #440 which has the most correction. Not inexpensive at $39.99 for the insoles, but a lot cheaper than the custom orthotics ($300 to $500) my orthopedic Dr. could get me, and Insurance does not pay for any of it.
I purchased the Dr. Scholls insoles, put them in my shoes, and felt a big difference right away. I used them for several days, and went back to Wal Mart, and bought three more sets for my other shoes. Not sure if they will help you, but it might give you some relief with your flat feet. It made a difference to me, and I am walking three miles a day now, trying to get ready for my Elk hunt in October.
There is a $10.00 coupon available online and once you send it in with the original receipt, you will get a check in about 4 weeks.
Good luck !!