My stock i5-750 temps vs Hyper212+ I bought (Speedfan)
Stock idle - 32degC Hyper212+ idle - 24degC
Stock load - 64 degC Hyper212+ load - 44degC
Stock cooler comes with three strips of paste. Upgrading to a new cooler probably will mean taking the motherboard out of your case to fit a backplate. However, the actual fitting is not too strenuous. Watch a youtube video prior to installing and you will be fine.