A colleague of mine also experimented with ElasticSearch on Azure. His server got hacked and was shut down by Microsoft after they discovered it generated large

A colleague of mine also experimented with ElasticSearch on Azure. His server got hacked and was shut down by Microsoft after they discovered it generated large amounts of traffic and participated in DOS attacks. (there was a vulnerabiliy, and many ElasticSearch servers were hacked a few months back) So I'd argue that using Azure Search Service, being managed, will free you from worries of having to manage and update yet another technology.