Woo! I've since found out that the XR55 will actually Tri-amp if using a Bi-Wireable speaker
XR55 Tri-amping
Basically, if you are running in stereo mode the receiver defaults to Bi-Amp if you are using the B Speaker terminals. If you also turn on Bi-Wiring, it will make the Speaker A terminals your high frequency with a dedicated amp, and the Speaker B terminals will Bi-Amp the low frequencies. How cool is that?
Now if Dave will just e-mail me my tracking number so I know my two 340SE's and STF-1 were on the way!