Since 2003, I've been with various ISPs: Nildram, F2S, Zen, UKFSN and O2 (the Home Access package - since Jan 2010). And I have to say unequivocally that O2 is by far the worst ISPs by a clear light year.
Fist of all, they send you a router that is only WEP capable (NOT WPA2).
They practice strict port blocking/traffic management (25 and 119 for a start), Bittorrent is horrendously slow (and I mean legal ones), their service is extremely unreliable, the speeds are soooooo slow that even listening to internet radio is choppy and painful. As for flash video....well.....!! In the evenings and over the weekend, my speeds are a laughable 512-1024 kb/sec.
I am in the process of moving to AAISP - so far, they have been extremely professsional and punctual. They don't block any ports, and they have generous download allowances. (O2 may offer unlimited downloads, but at their speeds and reliability, you will struggle to hit more than 30GB/month!).
Unless you are an inveterate masochist, avoid this horrible horrible ISP at all costs!!!
Goodbye O2 and good riddance!
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