Speccy takes your computer and scans it into something you can easily understand, or at the very least something someone can understand.

The interface is easy enough, just click on the column and stare at your computer. You can expand or collapse what you want with those triangle things.
The usefulness on the overhand... yeah, unless you want to know what type of computer games you want to play or you are upgrading your PC and don't want to look through your mountain of computer papers for something small, don't even bother with this unless you are a computer nerd and want to know the DRAM frequency on your RAM is.
The actual loading time for the parts is quick, only two or three seconds at worst for the RAM, motherboard, or CPU; considering how much it does read.