Upon further testing, the only items that fail are items over 4096. What happens with them is: If I do an "/lb redo" command, any items over 4096 will be recovered but are invisible place-holders. You can break the invisible blocks and get the item back, which is okay but less than optimal. There aren't many blocks over 4096, though, so it's not a big deal for me. In fact, the only ones I can find quickly are pipes from Logistic Pipes. I was also using some battery block that was item ID 9000-something and it had the same problem as the pipes.
All-in-all not a huge deal. I imagine if the items over 4096 were not placeable blocks, they would restore properly. I will test this later if I get a second, like just delete a bunch of items out of a chest then try to restore them.