So far I have been very pleased with my Liberty beans. I've kind of turned the herbicide management over to my son in law so I don't remember all the details.  Listening to others the tricks to a LL program include:

ALWAYS put down a pre-emerge.  Doesn't always have to be pre-plant, but must be pre-emerge. 
ALWAYS put down a grass killer.
Spray too soon.  If you wait until you think you need to spray you waited too long.
Read the label like reading the Bible.  Don't skip over any of it and if it says it do it.
You want the water wet soft and sticky, That means a lot of alphabet stuff: AMS MSO, etc. If you need to add something toolbar your pH do it. You'l want a surfactant to reduce surface tension and probably a crop oil to make it stick.  
Coverage Coverage Coverage. Lots of water in lots of places.

Oh and a neighbor says stand back because the darned Liberty beans grow twice as fast as Roundup beans.  I didn't argue with him.