RE: 5.9 VS 5.7 Hemi
I'd say, other than the peak torque and HP already mentioned, the LOCATION of the torque in the RPM curve is the biggest difference between the 5.7L HEMI and 5.9L engines. I have an '01 Durango 5.9 R/T and an '04 Ram HEMI. The Durango can accelerate at 1,100 RPM comfortably while the HEMI only feels comfortable above ~2,000 RPM. Peak torque on the 5.9L comes 1,400 RPM sooner than the HEMI (3,000 RPM vs. 4,400 RPM).
I love my HEMI and am going to keep adding performance bolt-ons to it, but IMHO, the HEMI drives more like a racing engine while the 5.9L "360" engine drives more like a low-end grunter.
Disclaimer: My first Ram had the 8.0L V-10, so I may have a warped sense of (torque) reality.