I tried this and I am very surprised how good Midi-Guitar is. Much better than hardware guitar to midi converters.
I use Guitar audio -> Line 6 audio Asio driver -> The Midi Guitar standalone software -> loopMidi driver software -> Sonar -> Any software instrument -> Sonar audio output to M-audio Asio driver.
Just super fine with low latency and very few ghost notes. Some small bugs (this is beta 0.6). Workaround is to start loop midi first, then Midi Guitar and assign the output to "Loop midi" before using "Loop midi" as midi input in Sonar.