I ran a holosun for IDPA. The advantage of the circle dot was I knnew for close range to use the bottom of the circle. But I started getting distracted by how busy the reticle was. So I switched back to a c-more and for close range head shots just aim for the top of the target. For center mass shots at close range I zerod the gun so if I forget to aim at the top of the down zero area I have enough forgiveness in the offset to still be within the circle.
As for the rifle I own both and they are both great guns. I find for me follow up shots are way easier with the mpx, it takes zero effort (that's with a tungsten weight installed on my JP on the barrel positioned right next to the receiver to help reduce dot bounce). I found the recoil on my JP ultralight out the box to be about the same as my first PSA pcc (fit, finish, functionality and reliability on the JP is way better than my psa). I guess shooting my mpx for months prior while waiting for my JP spoiled me. I recently installed 5 tungsten into the buffer on the JP to slow down the bolt and it has vastly helped in softening the recoil and improve my follow up shots at speed, but it still takes more effort than my mpx (I don't reload anymore I shoot factory blazer 124gr and 147gr). I use the JP as a backup gun in anticipation of the Mpx failing and having to be diagnosed.