I've used the solution for a while. I've used it for ten years. 

We have been using Symantec Secure Web Gateway for two years.

We have been using this solution for more than ten years and simultaneously use it with Comodo. We use Symantec Secure Web Gateway's latest version but only Comodo in some systems. It is deployed on-premises.

I have been using this solution for four years.

We have been working with the Symantec Secure Web Gateway for one year.

I have used this product since 2014.

I have been using the Symantec Complete Website Security solution for about six months.  

For website security, I worked with it for only a year when I was in Symantec. We supported a few customers who had purchased this product.