Mine is a positive story though. I never get outages and get download speeds of around 64-70 kbps max and generally around 50 kbps. I have a 512 Unlimited connection and cant remember when the last outage was :S . I had an ADSL Connection from Tata and that was very unstable
....... But Wimax has no outages. 
I wish I had better speed though.
Is not 50Kilo-bits-per-second (kbps) still very low speed on a 512kbps connection? Which city are you located? The general problem in our country is that the planning (if there is any at all) is bad.
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been using WiMax since last one year. No major Problem. Getting Good Speed since i migratd to WiMax connection. See my Test on my signature
Asking the same question - what plan are you on and where are you located (city)?