I have been using siteuptime.com for several months and would highly recommend their service. I recieve emails and text messages to my cell phone if there are any problems with my servers. I can't think of a false/ positive alert while using them.
I use the 2 minute service on SiteUptime, why pay the stupidly high Alertra charges, when you can have basically the same service for a tiny fraction of the cost....
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