[quote]1. Are you willing to pay for better service or do you want something free?
2. Where are most of your users located?[/quote]
[quote]1. So, the free one is not a good service ? Ok, both of them if I may ?
2. My targeted users are China, South East Asia, and US.[/quote]
I use mon.itor.us, which is free and will hit your site once every 30 minutes from three locations and give you response times and nice graphs. I couldn’t find anything more frequent for free and mon.itor.us was the only free one I could find that gave me response times instead of just site outage notifications.
They only have checks from three locations - in Germany, Austria, and the U.S., I believe, but you should check out their more recent info for yourself and also check out what they do better for their free service.
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