I was also having wifi issues since updating to 4.3. I get the message when turning on my network "Checking the quality of your internet connection." It then fails to connect and the notice is "Network disabled because internet connection is slow."
I found what the problem was, I went to Advanced settings within Wi-Fi and unchecked Auto Network switch. This took care of my issue.
Hi JB01 - Let's make sure you are able to control the way you want to use data! Is this happening on multiple WiFi networks or only at home? We can determine if a reset will be effective by running Safe Mode to see if you are still getting the same messages while connected. Here is a link with instructions: http://support.verizonwireless.com/support/devices/knowledge_base.html/77504/
I look forward to positive results!
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