I don't know how SimpleDB works in details, but as I understand here the channel is used as the "db" name sort of? Is this unique per account, or can you have multiple SDB "keys" per account? I ask because the channel in symfony2 for example is very simple/abstract stuff like "db", "request", "app". If you have two apps they would start colliding which may not be wanted. I think it would be best to allow the db to be specified in the constructor, and perhaps append the channel to it, or allow the db to contain %channel% in which case it is replaced by every record's channel?