The Sterling isn't Musicman's budget line is it? I can't remember the names of their different lines. The MIJ Ibanez in general are very nice guitars.
Musicmans tend to have narrower necks although this is a signature model so it might be different. The Ibanez on the other hand will have a very wide flat neck. I would be inclined to take the MM if the price of each was roughly equivalent based on the fact that I don't like floating trems but this is really a subjective call as the guitars are pretty different, it's not a question of which is better really.
If you're into EVH type trem work I would think the locking trem on the Ibanez would be better for you. It depends what this guitar is going to be used for, really. They're so different...