My two cents worth.
I fly enough to be PreCheck most of the time, but always use my Clear card. I fly from MCO and DEN and in both places it's easier and faster to use Clear as the Pre lines are getting longer now days. At MCO they usually put me into the Pre line if I have that on my boarding pass and I think Clear is adding that as a permanent feature at MCO. I literally chuckle to myself every time I go thru security using my Clear.
But admittedly, if you only want to pay for one, Pre is more widely used (I fly from DFW all the time too and only have used Clear once because of the location of the kiosk).