My biggest complaint about LI is their stats.
Your server will say you served 1000 ads. LI will claim they served 30% or so more. I challenged them on this since I have robust servers for the volume I was doing and they claim that perhaps people were closing the ads before they loaded, etc.
A certain percentage will be that- but I won't run anything with them until this is fixed. Fortunately I have other things to concentrate on.
In comparison TV has a loss as well but it's in the low % - like 1-2% usually. Rarely does it go over 5. Typically if it does your page load time sucks.
