I don't have specific experience with the Hamilton County system (never monitored it), but I live within range of the Delaware county system which (from what I understand) is pretty similar to the Hamilton County system.
That being said, I have problems with the Delaware County system on a regular basis due (I guess) to the simulcasting. The non-technical explanation is that since there are multiple signals coming at your receiver from multiple towers it can result in decoding problems if there isn't a single tower that has a stronger signal than another. If it were an analog system, the result of this would be weak sounding, fluttery signal. Since the system is digital, it means that the data gets garbled and the scanner isn't able to decode it. Like I said, I have this problem all the time, and it really depends on where you are in relation to the simulcast towers. My house, apparently, is in an unlucky location where more multiple transmitters are competing with each other, resulting in lots of "Medic 3..BUURP...et..respond...BUURP...accid...BUURRRP...23....BUURP...road".
This problem is not an issue of course with systems that do not use simulcasting.