I have been wanting to weigh in on this debate, but have been too busy to do stop. While my experience primarily lies with SATCOM and wide band communication systems, the principles behind the modulation is the same. In reality, digital modulation techniques are more reliable than analog, but had a greater dependency on the received signal strength. An analog radio will continue to pass "data" no matter how bad the signal to noise ratio gets. It just allows the noise (ie static) to pass through as well. This is why squelch is so useful, it sets a cut off point. Digital modulation does not do this. If the link margin gets to 0, you're done, but the quality is better and generally it takes less power spectral density to achieve the same range as an analog waveform. I don't have much more time to elaborate, but in simple terms, digital will perform better in most cases.