Sure thing, Delta and CQR often drag on their sides: Test Videos | MantusAnchors
But they have the possibility of setting, they are designed to dig in that orientation.
However, a Mantus or a Rocna or a Manson Supreme or a Bruce for that matter, if upside down are rendered useless... The Roll bar reorients the anchor into the right position for setting....
Given that Mantus has really wide ear tabs the likelihood of it flipping upside down is low, but exists... so we recommend to use the anchor with the roll bar and you will have a reliable and immediate SET in any terrain.