Yes the ReAction AHI prefs is really much the same as the MUI one, with the obvious ClassAct vs. MUI differences. So dont worry.
I also declare myself not a good fanatic of MUI, but i have to recognize that for some reason that eludes me, the same app both on MUI and ReAction, works faster with MUI. With ReAction there is a noticeable slowness in the way the GUI for any program is built when executed, something that when using MUI, is almost instant. If anyone can shed some light on this subject, i will apreciate!