so what is the recommended procedure?
I'm guessing backup the host, then destroy the obsolete host, then create a new host with the new specs either at the same site or at a different one ( I'm not sure if it's possible to say backup in Silicon Valley and restore in London )
@vrhypnosis If you snapshot, and create a new host with the new specs from the snapshot, it will be no different than if you just upgraded the original host -- you'll still have the same filesystem geometry of the old disk on the new disk, and will still need to use some sort of filesystem resizing tool.
So, it's still back to whether you trust the resizing mechanism of your OS.
Personally, when I've upgraded, I've created the new disk and partitions manually, then copied the files over, rather than extend a disk that wouldn't then match my own sub-partitioning setup.
As for snapshotting and restoring to a new server of the *same size* disk, that works fine, and also, to answer your question, can be done across locations - handy if you need a server ASAP and your prefered location is temporarily out of stock.
You could try - even if just as an initial test - snapshotting the server, restoring it as a new server, and seeing if the resizing works as you expect. But personally, I think it's voodoo that may come back to bite you in the future, long after the oroginal server has been deleted!