If you only found a DMG for 10.9.0 or 10.9.2, you must update to 10.9.5 immediately. Safari, security, and stability are vastly improved.
A corrupted DMG can result in a failed installation or, worse, system instability. If downloading from a third party, always verify the file checksum (SHA-1 or MD5) against known good values. This ensures the file hasn't been tampered with or corrupted during upload.
Malware authors love repackaging old OS installers with spyware. Before you mount the DMG, verify its integrity.