Neither are better.

The MusicMan is cheaper off the shelf, but if you get the inlays and piezo option, they cost about the same.

MusicMan JP - 1, 500 USD MINIMUM, add to that inlays and piezo, and it's about 2, 000 methinks.

Ibanez JEM - 2, 100 USD.

Anyway, I'd still get the JEM.
It's true, this stuff I make up.
I've played 2 of the Jems and the Petrucci and like the Petrucci better. The body shape is more comfortable for me. Also I like the neck on it better. Its hard to explain the difference between the two necks but if you play them you can tell. The Petrucci also comes with the Piezo option which is great. A petrucci with piezo goes for near $1800 while a standard one is about $1500. The Jems vary in price but I think are more expensive than the standard Petrucci sig.
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They are both amazing. For 6 strings, I prefer the JEm, for 7's, most definatel Petrucci.
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I love any JEM in terms of playability.

The type of bridge that you prefer should be a big factor here also. Also consider HH in the petrucci model against HSH in a JEM.

"Do you want a floyd?" and "what type of pickup configuration do you want?" are the most important questions.
The JEM, definitely. Much better neck (the neck is ****ing genius), HSH, FR, and it looks better IMO. Better pickups in general too.
petrucci by far, for me. the sounds you get from it are more to my taste (the petrucci's middle position is much better for clean than any combination of the jem's HSH), the petrucci bridge is a PHENOMENAL work of engineering (fr like results from a pseudo wilky type trem), the neck feels better in my hands, and it doesnt look quite as cheesy. add to that the piezo option, and it is petrucci hands down for me.
EBMMs are the most underrated guitars ever
most people never play them and just judge them randomly, but not only are the teh shit, but well thats it, they rock!
i ordered a silhouette special (HSS, woulda gotten w. piezo, but it isnt available for lefties, and im still waiting for those damn california EBMM factory hippies to finish it) and from the righty models i played, i can tell you you can get such diverse tones, and oh the neck! its like and orgasm for your hand!
you cant go wrong with an EBMM, the only downside is that i found out that when they have backorders and are working overtime to build all the guitars, they put the lefties lower on the list supposedly, so i have had to wait for 2 months so far and it has a soft ship date of april 8
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Jem Ftw
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