This is slightly difficult to explain about what locations show for our proxies, but here goes my attempt without giving too much secret stuff away...
Our proxies are directly routed through our physical servers but they don't normally show up as being in the same location on a whois because of the nature of how we purchase these cblocks. The original owners of them still show in the whois info, along with their physical locations, and that tricks 99.9% of sites into believing they originate from somewhere totally different to where the servers actually are.
So every block of proxies we have normally shows a different location, so I think you'll be fine. We do sometimes have to drop cblocks for whatever reason, like being blocked for various social networks, but that shouldn't really affect you as 80% of people on the planet are on dynamic IPs and they change anything up to hourly anyways so places like you mention shouldn't have a problem with it.
Thanks!