We (MongoHQ) do lots of sharding + replica set admin. Sharding is finicky, but we've found replica set admin to be really straightforward. Getting client apps

We (MongoHQ) do lots of sharding + replica set admin. Sharding is finicky, but we've found replica set admin to be really straightforward. Getting client apps configured properly is the hardest part of replica set use. It's only a one time problem though.