The issue comes as this: The factory is large. I have rows of 5-high stacks of auto-craft tables. I have lots of Logistic Pipes. What is the impact of this to the server as opposed to AE? I'm not looking forward to converting the whole mess, or even half of it, really. It does what I need it to do. However, the server is struggling even when no players are on-line. One Quarry and a few chunk loaders and I get "Server cannot keep up!" warnings.
AE will always be slightly cheaper than LP (LP does pathing, AE doesn't have to), but this is offset by the fact that LP often has mod-level optimizations for solutions like inventory regulation and liquid supplying. These solutions are usually more optimized than the more granular tools offered by AE.
Remember that you can use both. You can easily provide from the AE system into LP networks.