replicate or multi-master for 9.1 or 9.2

We have a new pg system on 9.1, just launched inside China. We now know we may need to run a replicate, with some writes to it outside China. Would like some advice. Here are parameters:

1 - Our data center is in Beijing. If we have a replicate in a data center in California, we can expect the bandwidth to vary between the Beijing and California servers and for any connection between the two servers to break down occasionally. How well does pg replication work for suboptimal connects like this?

2 - Is multi-master an option to allow some writes to the otherwise slave California db?

3 - Would trying this on 9.2 be a better place to start? I don't think there is any reason we couldn't migrate up at this point.

Although I've used pg for quite a few years, this is my first trip in replication land…any advice would be appreciated.

thanks

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Jon Hancock