Now you cannot find a driver exactly for your Video Card. For example if you have nVidia 8500 GT, you cannot get a driver exactly . Instead you will get a driver which fits universally for the nVidia 8x Cards. All cards which come under GeForce and 8x will have same video driver.
Notable Advantage is, single driver for a whole set of related video cards, so that even upgrading to the same series will make you to use the same driver.
File Size is the biggest disadvantage.Before UDA adoption, size of the driver file will be around 27 - 30 MBs. Now UDA drivers weigh around 160-180 MB.