For 13EUR/month I sure could get faster speeds, but also fairly small data limits. Here I get 300GB/month.
Maybe the nearby cell towers are overloaded, I don’t know. But at midnight it can go up to 45Mbps. The speed peaks around 2-3AM.
Also there’s the free national roaming in Orange 2G/3G network. So if I really need faster internet speeds, I can use Orange 3G HSPA+ which is pretty reliable, although with 20GB/month cap.