Updating Firmware & Drivers on IBM x3400 Server

I need to upgrade some firmware on my now aging X3400 server and am thinking about using the IBM UpdateXpress System Pack. This is available for running on sles 11_32-64. I think this is the most recent installer and since I have been an openSUSE user for some time I wonder which openSUSE release corresponds most closely to SLES 11.
Does anybody have any experience with this IBM tool and what are the likely issues if I try and run on an openSUSE release?
Budge