V10 WITH HEADERS SOUNDS LIKE A V6.
ANY BODY USED MUFFLERS WITH A BETTER SOUND?
I HAVE USED MAGAFLOW,WALKER,FLOWMASTER AND DYNAMAX. THEY ALL SOUND LIKE A V6

I had a Flowmaster on my V10 Ram. It didn't sound great,and I dislike Flowmasters, but it worked and was cheap.

But...from what I hear a V10 will never sound great but it makes a big difference to spend less time on the muffler and more time adding a crossover pipe between the two banks.

headers make a difference with any muffler deeper sound

Kill the caps BUBBA. You don't need to yell. It's the cap lock button on the left side of the keyboard.

You need a muffler designed for either
a 5 Cylinder inline (Mercedes)
or for V10 (Volkswagen diesel V10 or Ford gasoline V10)

These special 5/10 cylinder mufflers have a special sized 'Helmholtz Resonator' section of the muffler. These mufflers will probably work better if you mount them as far back as possible,
with little length of tailpipe.

As you have already found
the simple straight through performance mufflers
will all sound raspy with an odd rhythm

If you don't want to spend much additional money
consider buying 'resonators' and putting them mid way in the lengths of tail pipe you have.

Know a friend or family member who is extremely good at math?

Here is how GM trained student engineers on how to get rid of both exhaust (and intake) noise:

http://paws.kettering.edu/~drussell/GMI-Acoustics/Filters.html