EQ, for me, falls into the category of a must have. Prism99 is correct however - it depends on what you need as a quilter. I enjoy the ability to change the block settings, play with sashing, build borders that look proportionally correct, resize blocks and the last biggie for me is to be able to turn just about any pieced block into paper pieced.
That being said, some have said that it was difficult to learn. I myself did not have much of a problem and I use it all the time - but even with the frequency of use, I still only utilize about 50% of what is available in the program. I am always learning.
It is a pricey item and there are some less expensive options out there. If you are able to attend either a sewing or quilt expo often they have demos of these types of quilting programs and you could see first hand what each of these products do can compare them first hand. Also - is a quick google check - there is even and online quilt design
program you can subscribe to for $9.99 a year