Time for an oil change, can I switch to synthetic, is it worth the extra cost, which is the best brand?  Any help with these questions would be appreciated.  

i changed to synthetic, and don't regret it.  I used royal purple i my xj and mobile 1 in my tj.  royal purple is very expensive now and mobile 1 seems to do as well.  Both jeeps seemed to have better start up idles on cold winters .  

I am running my 07 Wrangler on Synthetic for about 2000 miles now. Its still the same color as the day I put it in. Hasn't blackened at all. I would definitely recommend it to you.  

one of the problems with oil that never blackens is its a tell tail sign that its not keeping the engine clean,
good oil has high detergents that collect contaminates and gets changed often even though they say ya can leave itn for 25,000 miles, not a good idea..

for example the bad rap penzoil gets for sludge.... It's not the fault of the oil it wasn't changed regularly.  

There is no doubt that synthetic does not break down as fast and is not affected by hi operating temps as much.

Running synthetic in your engine is debatable. While it will last longer, it still gets dirty in a dirty environment. Leading to an "early" oil change with regard to synthetic.

If you run hi way miles, synethic can remain in for longer periods. But, dusty, city, offroad miles... any oil will need to be changed more regularly.

That starts to make synthetic really expensive. If you use petro oil and change it often, it will lend the same longevity to your engine as synthetic. And probably for less money.

Trannys, TC, and diffs are a different story. They don't operate in a dirty environment. So, the oil doesn't get dirty very fast. The failure is the loss of lubricating properties becasue of "use" and heat. A perfect environment for synthetic, for sure.  

yep....