The most important thing I like is that it can be run anywhere, i was able solve many issues related with our websites performance over time without having an expert help in this area but thanks you now we have someone who knows what he's talking about!The UI could use some improvement for example make easier access some areas of configuration such as adding new reports or add more report types/options (i think there are not all available atm).But otherwise good product so far The best thing about testo is that it's free, so there are no costs involved in using this service! It also has an excellent customer support team who respond very fast when you have any questions or issues with their software (and I've had none!).
We use teto for our website monitoring as we're constantly testing new features of my client websites - which can be quite time consuming if done manually by hand each day/week etc..