At home I have a Linksys EA4500 (don't quote me on that) and at work we have a Cisco Wireless system all over the building. I got my S4 about two weeks ago on Verizon's roll-out day. I had problems connecting to the WiFi at work and at home. It would connect, disconnect, connect, disconnect... for several minutes before finally connecting (or not.) I was ready to return it and get another unit, but decided to do a factory reset (from the recovery menu) because I knew they would try that at the store. After rebooting and getting everything set up, I have had zero issues connecting to WiFi. It jumps right on both systems immediately and stays there. The WiFi at home is lightening fast and the one at work is as fast as that system ever is. Maybe we should stop referring to a Factory Reset as "like right out of the box" because right out the box for me wasn't good. I hope this helps someone.