MsgFiler 3.1.1 is now available from the Mac App Store. This version of MsgFiler now requires OS X Mountain Lion. It fixes the problem where messages are filed slowly even when using the MsgFiler Engine.
Users of MsgFiler on Snow Leopard and Lion are encouraged to download and use either MsgFiler 3.0.4 (the last version from the App Store for Lion and Snow Leopard) or MsgFiler 3.0.5. Engine users should use MsgFiler Engine 188.8.131.52, for the best possible performance.