Is it really that much better than other oils? I use mobile 1 right now, what would switching to royal purple do for me?

 

Minor, minor differences. You would need a labratory or dyno to seea difference and that is not worth an extra $40 to the average enthusiast.

 

fully synthetic oils are mostly the same... save your dollars and stick with mobil 1. they make good oil too.
if you're interested, here's a great article about oil... it's long though.
Oil

 

Be careful with some of the newer oils, the API SM "energy conserving" and ILSAC GF-4 certified are all low phosphorus and may cause lubrication issues. I'd been running SL rated oil for a while without issue, after just recently changing to the low phosphorus crap(API SM "energy conserving") my thrust bearing burned up inside 1,000 miles. Apperantly I'm not the only person with this problem either. The reduced levels of ZDDP are causing all sorts of problems for some people. Mobil 1 0-40 and 15-50 still have decent ZDDP levels in them.

 

I didn't think that applied to fully synthetic oils... just mineral oils.
Since fully synthetic is very different from synthetic blends. Plus you don't want to run a thick oil if you don't need to. Only if your engine runs at a high operating temp (like when racing) otherwise the engine won't heat the oil to the right temp to be the right viscosity, which will only cause more wear and tear and less power.

 

The phosphorus and zinc levels apply to all oils now that meet API SM energy conserving certification, and/or ILSAC GF-4. That being said, I went out and bought a case of Valvoline VR1 30wt, which has ZDDP. The new GF-4 standard requires 800ppm or less of phosphorus. It's aggrivated the problems with flat tappet cams even more than they already were.

 

after putting royal purple in my 06 mustang it seemed to idle alot smoother.. dunno it might of been just me lol

 

I think it might have just been you. lol Your engine isn't old enough and doesn't have enough wear on it to be able to tell a major difference in oils. I think that Royal Purple is a good oil to put into an older engine. I have put them into some older engines and you can definitely tell a big difference.