The price of that RJ45 is pretty hefty
![Shocked :shock:](./images/smilies/icon_eek.gif)
But compactness is costly so I'm not surprised.
The PoE module is a good idea, however I found that not many people use the 48V system, because of the cost of converter modules. Instead I found that people use 12V or 24V, (most cameras use 12V and not even isolated DC-DC
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
) which is much cheaper to get the DCDC modules to convert it down to 5V or 3.3V, and also you can buy 12V ans 24V adapters anywhere. 48V? Not really. The whole signiture thing is... I think the actual standard is only used in industial situation, most makes don't buy that expensive stuff. Technically you can put any voltage on the PoE pairs.
Disadvantage is of course the voltage drop, which increases by cable length and current, but using more than 1A is a rare occasion, and under that, the drop is within the limits even for a longer cable, say 20m.
So adding an actual PoE module, is a plus, but just anoying additional cost. But this is just my opinion.