When the heads are off, check the threads in the block for looseness or wobble in the bolts. In my case the previous owner (or his garage) had clearly tried to fix a warped head & gasket issue by overtightening. 40% of them needed helicoils so I got them all done.
ARP studs are simply easier because you tighten the stud in the block using an allen key, and then apply the ARP greas to the stud threads & washers before doing the torque. They also only require 60-80 ft-lbs so easier to get it right.