Frankly speaking, whether you use an RL/RDP/sBorg which ever thing it may be, when you upload to file hosts like Fileserve and Filesonic you will have to choose US come what may.
US server is the best for faster uploading to FS and FSO as they are also located in the US and surprisingly RS will also give good enough speeds on an US server. When you are only uploading on RS then you will have to choose an NL servere where RS has awesome upload speeds.
NL servers don't have enough speeds on FS/FSO compared to US and they even suck sometimes.
So choose US if you are using a combination of FS/FSO/RS and if only RS then NL.