I use clonezilla exclusively for my imaging needs. The DRBL server does take a bit of research to get going, but once it's going, it's been very dependable for me. I have a 64 bit Ubuntu running DRBL on an HP Z400 workstation. I have a small standalone network in my lab with a Netgear switch and an Avocent 16 port KVM. I can do a batch of 16 at a time and then switch the uplink on my switch and connect to the live network join our domain and get updates if needed. My record using this method has been 208 machines in a single work week.
I also put clonezilla on bootable usb drives and gave them to my field techs. They can have a user working again in about 30 minutes.