Metal-Oxide-Scmiconductor Field Effect Transistor (MOSFET) has been the major device for integrated circuits over the past two decades. With technology advancement, there have been numerous MOSFET structures for channel length of 0.1 /um and below reported in industrial research. A side-byside comparison of these advanced device structures can provide useful understanding in device physics and the design tradeoffs among MOSFET's parameters. In this work we employ experimental data, device simulation, and analytical modeling for device comparison. The devices were developed at several different research laboratories. Guided by experimental data and simulations, analytical models for topics such as threshold voltage, short-channel effect, and saturation current for these different MOSFET structures are developed. These analytical models are then used for optimizing each device structures and comparing the devices under the same set of constraints for a fair comparison. The key design parameters are highlighted and the strength and weakness of each device structure in various performance categories are discussed.