We implemented AMP version of https://www.tarafdari.com two weeks ago. During this period we had 3% growth in session but 15% of real-time traffic comes from AMP.
This is important to us because of our contracts with advertising companies.
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If you have both of them, than yes. On having mobile version and AMP your AMP version will be used only for some special AMP-ized placements, like caroussel, top stories and the like. In this case you should keep in mind issues like placement of advertising (splitting), avoiding of duplicated content etc.
If you have only AMP as your mobile version, than Google will use it as your general mobile version. In this case you drive securily without any issue, caused by two site versions for the same purpose.
My personal way of choice would be to maintain AMP version as the only mobile version: this approach seems to me to minimize managing afforts. If your site doesn't sell (as far i can understand, maybe beside of subscriptions) you'll drive securely and without feature losses with AMP as the only mobile version.