I haven't had this exact combo but have been close - on my 2014 Ram I had a full bedrug with an ARE x-series topper and it was an awesome combo that worked well for hauling mulch, dirt, gear and for general camping use (sleeping in back is better as the bedrug keeps down condensation and is softer. I did not have a spray liner in that truck but the bedrug is compatible with a spray-in liner with a slightly modified install. I have the bedrug mat with tailgate piece on my 2021 with spray-in liner under another ARE topper and it is also great. This last time I skipped the full liner for the mat as I didn't think I needed to protect the bed sides with a spray-in already there but wanted the cushion and anti-slip on bed floor. If you decide to go with a full rug and topper I highly recommend ordering your topper with a full headliner so to cut down on condensation if you plan to camp and also to improve the look as the headliner will match the bedrug. I couldn't find a pic from my old truck but here is the topper and mat.
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