The budget of 5m seems to be pretty low as opposed to a single U.S. county system upgrade. Any thoughts on this?
Well that depends on the county and how corrupt they are. See, in America, money influences the politicians who buy the radio systems. When you buy the politician, the politician buys your radio system.
But that said, the proposed Isle of Man system would ring in at approximately $90 USD per capita whereas over here, the average is $72 USD per capita. While it may seem strange to calculate it per capita, it's almost uncanny how the majority of them seem to be priced at that same level so I keep doing it. So I hate to say it, but that proposed system is a great deal more expensive than the average race-to-waste digital trunking system in the US. I would suggest that if you are local that you bring this up to your local elected representatives and ask them why they feel it is necessary considering it's a very small island, mostly uninhabited and the small populated area has quite a small population. A $3,000 USD repeater system would probably be more than adequate.