... ISP's shouldnt be allowed to oversubscribe areas and if they cant give everyone 50mb they should give everyone 20mb and not throttle people who are heavy users.
Well there is nothing wrong with having contention in a network, they couldn't sell their product at the sort of prices they do otherwise.
Managing it correctly is important and ensuring the ratio is not something ridiculous, this is where VM and just about every other cheap ISP fail to manage things.
And at the end of the day VM are a cheap consumer ISP, and when you're charging most of your customers less than £20 a month for access it doesn't leave a lot of money left over to reinvest in the network.
Especially when most of them probably don't notice or give a **** if the service isn't brilliant and most probably don't use P2P applications.
Whilst a high volume of P2P traffic is going to likely be illegal file sharing it will also be generated by a very small number of users, so taking measures to control it will in most cases have an impact for good for most of their customers.
Quality of service and maintaining a congestion free network IMO isn't viable for companies like Virgin, TalkTalk, AOL etc. (even O2 are feeling the effects of whoring themselves out at the lowest price now).
Sure it would be nice if people like VM et. al. would actually do something about the quality of the service they provide instead of chasing ever higher headline access speeds but that isn't going to happen, internet access has become a commodity service - something that is given away free with a mobile phone contract and now because of that most people won't be prepared to pay for it at all, or at least not pay very much.
Most people are incredibly ignorant about how a network functions and they only just about understand one quantifiable value and that is throughput. Factors I consider to be important for my needs like latency, jitter, levels of packet loss etc. don't mean anything to most people, and it is that lowest common denominator that companies like VM are targeting.
If you want no congestion, low latency and jitter, no traffic shaping and so on then look for a business grade ISP, but most of those aren't going to cost you less than £70 a month if you want to sit there doing some hefty downloading 24/7.