Memphis, have you ever stalled a PA28 with an aft CofG? Or just two-up (you plus instructor)? Try it. CofG position makes a lot of difference in stall/spin characteristics. It's also the reason that the PA28 in the "U" category has tighter CofG limits than in the "N" category. Fly an aircraft that has an "A" (aerobatics) category certification and the CofG limits become tighter still.
And remember if you fly the PA28 solo instead of dual, the CofG actually moves *aft* since the front seats are in front of the empty CofG. So stall characteristics are slightly more pronounced solo vs. dual.