There are many advantages to having an external DVD drive, and many disadvantages to having an external drive, and we will go over both so that you can decide which best fits your needs.
The advantages of a DVD Drive External USB…
Well the first obvious advantage is that they are mobile and portable. You can very easily move them around to wherever you go or to travel to.
Another reason why these external drives have remained useful is because of the advent of the super-portable laptop. Because with these ultra portable, ultra light, super fast laptops, also came the removal of many of it's key components. This for example may include the removal of a decent DVD-RW drive… Replaced instead with a CD-RW and DVD playback or the possibility of having nothing at all. This would thus make you purchase an external drive as a substitute. This adds a lot of flexibility because you can then take it if you need it, or just leave it behind if you don't need it.
Another advantage of these external drives is that they can be taken from one computer to the next computer, which is beneficial in a small office business environment, as well as shared within a household.
And if you're not tech savvy then you can very easily upgrade the external driver by simply plugging it in to the USB port, installing the software, and just like that your up and running.
The disadvantages of a DVD drive external USB…
Well for one thing external drives are more expensive than their internal equivalent. Also external drives are much slower at writing and reading discs than it's equally rated internal counter part.
Another disadvantage is that they take up extra space and need additional cables like power cable, Fire wire cable or a USB cable (no wireless solutions as yet).
And because external drives are moved around a lot you risk the possibility of it falling on the ground or getting broken thus increasing the chances of it crashing.
So, of the two which one is best? Well, very simply it comes down to each user's individuals needs and wants.