I've been with seedhost.eu for about a week now. I must say that they are really awesome.
On 10Gbps plan, the max upload speed I saw was... 199MB/s (yes, megabytes per second).
My support ticket was always replied promptly.
Before settling on the 10Gbps plan, I also jumped around different plans to test out the speed. They had no problem with that and always processed the refund promptly.