Generally, for a learning remote to learn, it needs to receive at least two consecutive IR signals. The learner remote uses the beginning of the second signal to define the length of the leadout. This is particularily important with Sony signals, where Sony12, Sony15 and Sony20 all have the same form, excepting the number of bits in the signal. If the Sonance is only sending one signal with no repeats, then the learners may have difficulty. Note that components themselves already know what kind of signal they are looking for, so they typically recognize a single signal.
However, with the RCRP05B and cable, you can load the
XDRF1HD upgrade , prove that it controls the XRD, and then use the Widget to compare to those Sony signals to the output of the Sonance.
You can also then compare the response of the Sony and, say, the DirecTV (use CBl/SAT 1377) as you increase the distance of the remote from the components, or interpose some partially transparent cloth. I think that would tell you if the Sony is less sensitive.