My 9 - 10 Mbps woks fine for the things I need - including iPlayer. Unless you expect to use it for a lot of HD video, I do not know why such high speeds are needed. They should concentrate on a more universal move to 10Mpbs in all locations. I would pay a bit more, say £20 - £25
I pay around £30 a month for 100 with VM which I get. I get unlimited downloads, if I were to use torrents which I never do I could get my speed capped at peak times if I exceeded a set limit for that day, I've never had my speed capped. I'm quite happy to pay the amount I do & personally consider it money well spent.