Some important points to choose for directories before submitting your sites:

- Unique design directory
- Offers deep linking option ( deep link directory ), at least three or more.
- If paid directory, choose the one that offers various price range for site review.
- Directory contains brand name or unique logo.
- Pages indexed by Google or other search engines, if you care about Google PR value.
- Site review time is less than one week.
- Customer service or support. The faster response, the better choice.
- Directory hosted in good or reliable hosting company which means less downtime.
- Directory does not content Google Adsense or other advertisement including pop up advertisement if it is free web directory.
- Directory owner or company has several sites (other niche directory or sites) in their networks.
- Directory has more than hundred back links in Google search engine.
- All the pages in directory are search engine friendly.
- And the last and most important thing is if you satisfy with the directory (design, contents, etc. ), you can submit your site without further thinking.