Pay for 100 MBPS, get 1 MBPS - pathetic!

I have had a contract with MWEB for a few years in Bloemfontein, few problems, actually recommended the service to a few friends. When moving to Cape Town, I subscribed to a 100 MBPS service, 200 GB per month, for just under R1000 per month. Since then, we have had constant problems, with Internet speeds as low as 0.6 MPBS tonight, 1-2 MBPS two days ago, a high speed of 6-7 MBPS yesterday. I have queried this, I have phoned, I have bought the best, most expensive router I can afford, with temporary speeds that went as high as 70 MBPS. So, in essence, MWEB makes you pay for 100 MBPS, but gives you about 1 MBPS. And when you make an enquiry, they DON'T solve the problem, so I am looking for a new provider!