Hi, as Forefont TMG is discontinued, UAG is too expensive.   Any good replacement at similar cost level?  

thanks

Please click "change type" and select question.

For what it's worth, UAG was also discontinued.  Most folks use their load balancers instead anyway.  For example, see Kemp's article on the topic:

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Microsoft also offers WAP (part of Windows 2012 R2):

Life in a Post TMG World Is It As Scary As You Thin