Only during peak hours which is 6pm to 11pm and speeds are just reduced not killed completely. Streaming for example receives more priority during those hours. Get a sim and you will have 15 days to try out the network and test it to see if it meets your needs.
Haven't had an issue with this. Only between 6 and 11pm it gets heavily shaped to about 150kbps. Otherwise goes well, that being said it might change as more people get on the network.