I have looked everywhere for this info, and I can't find anything conclusive. I recently purchased an RGR421EXFM (fixed bridge) which is on the way to me. I know the strings are D'Addario XL's, but I can't find the gauge, most people say they come with 9 - 42's.

In the 2008 Ibanez catalog, I did find this:

The first line there shows 9's for the tremelo guitars. Mine is not listed, but the RG321 is a very similar guitar, also a fixed bridge, which comes with 10's. In fact, all the second line are fixed bridge guitars.

Anyone know for sure?

I guess my only other option is to measure them when I get it, but I was thinking about ordering a few different string brands to try some out... I like to tinker.