I had LL corn probably 4 years ago.  The thing I didn't like about the chemical at that time was that the temp needed to be 80 above and the spraying should be done at high noon to make sure the weeds were actively drawing in.  Add in that they wanted 14 gallons an acre made it all a hassle.  Good kill and fast, but do you know how hard it is find a day in ND where there is no wind at noon?  They may have better products out there now, but that was my experience.