Original Xbox FAQ
Are original Xbox disc drives interchangeable?
The Short answer
Believe it or not the original Xbox disc drives are ALL interchangeable with each other. This means that any of these 4 original Xbox disc drives can be used in any version of original Xbox console regardless of the version. You should know of one small difference in the Philips branded drive. This drive is physically a little different in size. The bottom has a large "bump" that sticks out about 1 1/2 inches from the bottom. The other three do not have that. This may be important to some if you have mods that take up space underneath such as an internal WiFi mod or even certain mod chips. Otherwise That is the only difference.
You also will not need to switch PCB boards or re-marry the disc drive to the motherboard as is the case for many other video game consoles. There is no marriage, programming, or soldering required. In fact the original Xbox has the most interchangeable disc drive system of any game console out there! Simply place the disc drive in the plastic chassis, plug in the power and IDE cables, and you're done!