I've been using the solution for six months. 

I have been working with it for the last nine months.

I have been using the solution for more than six years.

I have been using ThousandEyes for a few months.

I have been using ThousandEyes for five years. Also, I am using the solution's latest version.

We have been using this solution for one year. It is deployed on the public cloud, and agents deploy on the public cloud, data centers, and end-users computers.

I have been using ThousandEyes for approximately six months.

We've had the solution for three years at this point.

I've likely used the solution for about six months at this point. It's been less than a year. It hasn't been that long yet.