Actually we are not selling anything.
We are just interested if you and other PC-users have ever tried monitoring services and noticed any drawbacks in their work
Lemme get this right... You have monitoring stations on four continents, (pretty much covers the known world), and your first press release was Aug 2004, (about 2 years ago)...

Logically therefore, you have a reasonable existing customer base so you should have all the feedback you should need from them regarding your service. The only other logical option would be that you have failed to generate a reasonable user base.

Either way you are "marketing" your product... Which is generally considered impolite... as I'm sure you are well aware.