I would happily chip in to a node like that. One thing, though, about USA is their fickleness when shown a legal letter. I increased VPSs to more than ten paid a year in advance with GreenValueHost because they were so helpful they even reinstalled Tor and sorted some Linux problems for me. Then they banned Tor. I can only imagine that their spines collapsed at a threat.
So USA can be fast and cheap but beware when they agree Tor is acceptable because there are poor trade practices laws to get refunds and rights.
Robert
I also share the thought that more US exit power is welcomed in the Tor network.
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Depending on your budget, Voxility has a datacenter in the US. Unfortunately they provide only enterprise class servers with prices directly proportional to the class. Maybe we can manage to pool $ in order to create a bigger node with this provider if we find enough people.