Ecovers can increase your sales and create a visual expression for your product. Your software or ebook can have good competitor in the market but a better ecover design can give your product more credibility.

Plenty of ecover designing software are available on web for download and use. These software have following points in favour of them:

One does need script language and design skills to design ecovers through software.
You can design unlimited ecovers by buying full version of a ecover design software.
You can get a full functioning software just by one time investment.
An ecover design software can quickly generate 3D effect on a 2D graphics.

In spite of their advantages, ecover software has few limitations:
Ecover designing software can come as plug-ins. You need to have original photo editing software for that. Like, you need to buy Adobe Photoshop first before using Photoshop plug-in scripts to make ecover.
If you cant design the face of the ecover image, it is better not to use ecover design software. No ecover software can design the face of the ecover. You should have the design knowledge to design it yourself or take help from other people.
Output in ecovers can be obtained in limited number of standard shapes. Changing shapes from software output will be difficult for you if you dont have the custom shapes.
Different software may have different using guidelines. If the user manual is too complex, you wont be able to use it as per your needs.
Different website owners can buy and use the same ecovers. Different software designed ecover output may be similar to look and get less attention from buyers.

For shoe-string businesses and for baby boomers, my suggestion is try an ecover design software. Beware of the above limitations of the ecover software before you purchase one.