My general, very blanket-level statement, experience is that booking with a virtuoso TA is much more likely to result in an upgrade (and more often at time of booking), than FHR, but that FHR always gets the late check-out which can be important and a few times, primarily in the US, the breakfast credit is more inclusive. A couple of hotels I have stayed at the breakfast on the Virtuoso could not possibly have accommodated us in full.