First, a quick correction: the company is (not Symantic). They are the makers of Norton antivirus products.
Would you like a comparison with another antivirus definition set (e.g., Microsoft Defender, McAfee, or Bitdefender)? symantic virus definitions
It looks like you're asking whether "Symantic virus definitions" are a good piece (of software/security). First, a quick correction: the company is (not Symantic)
Here’s a straightforward evaluation: