I can see good and bad with both the power wire and a cooler thermostat (and the two should NEVER be run togeter). In my case I'm running the cooler thermostat because I have lot of mods that lean out the mix as in LT headers, ported TB, CAI and a tuner who'se performance setting really advances timing a good bit.
So I either needed to go piggyback A/F controller or something to richen the mix. Since I was not a lot off specs the cooler thermostat was enough to bring me right where I wanted to be. Yes, the power wire would have accomplished it too, but I live in the deep south, I have no problem running 180* in winter.

Which brings me to the advantage of the power wire. In EXTREME cold, it does take a good bit longer to get the heater up to temp to warm the cab with a cooler thermostat, also, if 90% of your driving is nothing but short 1-2 mile hops running a cooler thermostat won't let the oil get up to temp as long and could result in condensation in the oil or even sludging.

Now if you're not in the extreme north or don't just take short hops IMPO it's better to just run the engine at a cooler temp than it is to fool the PCM. At least that's my take on it. Now I know quite a few guys who run a 180* t-stat in summer and a 195* in winter who live up north. That's also an option since it takes about 10 minutes to swap one in a Hemi (a bit longer in a 4.7 because it's on the bottom)...