Rains poor internet service

I've recently purchased a R479, 4G package from rain. I have made numerous of calls to them regarding the poor network service I am getting and often argued the fact that during the day I receive speeds at 0.2 mbps and in the early morning and late evenings it gives me +-10 mbps and I can't see how this is possible they talk a fair game about speed up to 10mbps but during that day it's so horrible. Many people say this a one of the best and cheapest networks but currently I struggle to see how they are so good.