Germany as a nation and economy is going to be much bigger. The Germans are essentially playing a very different game than the UK right now, by taking refugees in a controlled fashion they are getting an injection of cheap labour, much of it highly skilled. They are also getting linguistic skills and families that will work hard for little money and make something of themselves.
This additional 1 million people in 5 or 10 years will increase the size and scope of the Germany economy, improving its generally sluggish but reliable growth rate by injecting young eager workers.
Germany has a excellent industrial base, good education and good debt situation. The German problem is an aging population which is too conservative and too expensive.
The refugee crisis will make Germany look more like the USA, a larger population, younger, cheaper, harder working.
Its brilliant. It helps to transform Germany from the biggest nation in the EU to a more major global player on the world stage at a time when the UK is doing everything it can to limit its role and presence on the global stage. Without the UK and France in a weak position Germany's domination of the EU and its major voice in global politics is more assured with a bigger faster growing economy.