I have been using this solution since 2019. 

I have been working with SolarWinds AppOptics for the past eight years now.

I've been using the solution since 2015 or 2016.

I used the solution for a few years.

My company has been using AppOptics for a long time.

We have been working with SolarWinds for over five years. 

AppNeta has been in use for around a year and a half.

I've used it for two years.