Simply put the speed of flash memory versus a traditional spinning hard drive makes the SSD the clear winner for speedy boots and shut downs as are the read and write speeds extremely fast.
Then you move to energy consumption and heat which don't account for much in a desk top but the smaller and more portable the device the more it will help.
Now for the down side which has minimized by leaps and bounds since the early days of the SSD. Price and storage size, today most people are using these SSD's for the OS and software only while keeping data and none essential games and software on a large or several large HDD's or spinners.
Lastly the shock proof design of a SSD should in theory be much greater than a mechanically spinning hard drive.
In my humble opinion the SSD is the most trans-formational device with which I've added to my various rig and no serious computer today would be as functional without one. With costs of 60-80 gb SSD's well under $100 usd and 120-128gbs for around $125.00 it's a real no brainer!
