Check Proxy Professional (Socks)
Features:

1. Managing / checking SOCKS proxy lists
2. Proxy list printing
3. Determines speed of the proxy server
4. Determines Location (country) of the proxy server
5. Recognize different formats of proxy list (separated by colon, spaces, tabs, etc.)
6. Proxy finder (Proxy Hunter)
7. Supports multi-threading (can check many proxies simultaneously)
8. Check Proxy Professional is blazing fast. 9. It requires less CPU/network resources than regular proxy checking software.

http://www.socksproxylist.com/checkpsocks/