Slow Speed and Latency

I have a 10 Mb line and 50Gb capped account with Afrihost. The latency and speed is intermittently slow. Speed drop to 2-5Mb/s and latency 150-200ms. I have logged so many calls and they come back with the same old lame response. Reset port and reboot rooter. I also have a Cybersmart account. Everytime I enter my Cybersmart login in my router the speed is 8.7Mb/s downlink and latency is 10 ms. Do you think I get this into their heads. They cannot see that they are the problem. This is going on for a year. My fault history with comparative results is there for everyone to see. They could care less. It is all about the money. Typical American smooth talk marketing while they cannot deliver. They will only take your money and could care less. I gave up convincing them. I am really so tired and will cancel my service. I urge everyone out there to think carefully before sign up with Afrihost. There customer service is just as poor. I can actually not believe they get away with what they are doing.