@MrSoapSud - Just wanted to come back to say it depends on model computer for me. My Latitude 5480s sit at like 10-20 seconds on the loading .wim file, but on the 5470s it's a few minutes at that boot.wim stage. Going to troubleshoot and see if I can get to the bottom of it. Support said "I did find discussions around I-217, I-218, I-219 NIC devices.The discussion noted that these devices may need to have the firmware upgraded. So check the equipment manufactures and see if there is a firmware upgrade, it maybe a bios upgrade to upgrade the NIC controller"
Edit: both 5480 and 5470 appear to use I-219 NICs. Updating BIOS on 5470 didn't help speed it up. :(