I can't see the benfeits for most users to choose Be over O2. O2 is cheaper and uses the same network. The new white O2 wireless box II has solved almost all the previously mentioned issues with the old style black router. Mainly overheating and dropping the internet connection.
O2 customer service is second to none. They answer the phone within 1 ring, they're UK based 24/7 on an 0800 number. As Blitzen mentioned above the O2 rep can alter ping, upload, download, noise margins in real time whilst on the phone.
Also, how are people managing to download between 30-300+ Gbs a month?
Legal torrents I assume......