> Is there any way to test the speed to the EU data center?

Create a free Backblaze account in the EU datacenter region. Then upload/download some data! The first 10 GBytes of B2 is 100% free, you don't even need to give us a credit card so you can try it all utterly risk free with no way we could mess with you.

If you run the Backblaze Personal Backup, make sure you manually configure it to use 30 threads, then let it rip and watch your bandwidth meter to see what it can use. The first 14 days are completely free, again no Credit Card required! Personally I get about 100 Mbits/sec from my home in California to the European datacenter (capped by my ISP), but if you are in Europe you should be able to hit 500 Mbits/sec using the Personal Backup Client with 30 threads if you are close enough to Amsterdam (where the datacenter is). Oh, one hint -> don't judge Backblaze Personal Backup until you have been backing up for at least 12 hours. Backblaze backs up small files first, and the latency to push 1 byte files murders performance. But after we get through all your small files, it should rip.

In the end, everybody has enough bandwidth to reach everywhere in the world now, and you really shouldn't pick a service based on total throughput. I think you should pick it based on cost, comfort with the security model and how sensitive your data is, ease of use, etc. Unless you have a Petabyte or more of data, you can backup hundreds of TBytes to anywhere in the world nowadays. Easily. No problem.