This is one thing that I liked about CloudCMA (Now CloudAgentSuite) where the buyers get the instant listing alerts.
In this market, buyers and their agents want to be on top of the new inventory and grab it ASAP. You never know the buyers may get lucky.
This product is a part of the Cloud CMA Suite - and is known as CloudStreams.
As per them --
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Cloud Streams gives your buyers the fastest listing notifications in the industry - faster than Zillow, Trulia, Redfin, Realtor.com, and even your MLS.
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Disclaimer: I just am on trial for this service.