Comentário oficial
Sorry, but how do you see internal storage as being different or more convenient than external storage? The only difference is it would be located inside the hardware instead of connected to the face or by a cable - any storage would likely be via USB interface, and just as susceptible to failures or dropouts, and then would be incredibly inconvenient to update as you would need to connect the RX to your computer instead of the drive itself ... and then you couldn't use it with any other device.
If you're worried about the reliability and dropouts, get a good quality USB drive (either an expensive flash drive or solid state drive) and never look back.