I received my ATT iPhone 5 on launch day and immediately experienced the issues with WPA WIFI and the HSPA+ dropping to EDGE, then dropping to no signal. Exchanged it once. Same problems. Reset network settings - no help. Clean install - no help. New SIM card, no help. Got a second replacement, clean install...no problems for two days. Was playing with my settings, realized LTE was still "on" (my area doesn't have LTE). Not immediately making the connection, I turned it off. Several hours later, WIFI issues. Next day, cellular network issues. Lightbulb suddenly came on. Turned LTE back on, and have no experienced WIFI or network issues for two days. Battery is also lasting MUCH longer. Coincidence? Sure, that's a possibility. I haven't done any serious testing of this theory, but it seems to work for me. If you're experiencing similar problems maybe it will work for you too.