Rely on? No!
Firstly, you'd have to plan your route making sure repeaters exist, but even if you did, they're all run by radio clubs and the like, so may be off air for maintenance or due to a fault, etc.
In this day and age, if you want reliable remote area comms, a satphone is your best bet.
You could go HF radio, either via an amateur license or one of the commercial networks with a Codan or similar, but they're still less guaranteed than a satphone (as long as you can see the sky and are in a covered area for the network you've chosen, of course).
For pure "Help, come get me now" type emergencies, a PLB is also another (far cheaper) option too.
Just my 2c worth, and I have all the above options.....couldn't tell you the last time I bothered using the HF though, and it isn't even fitted at the moment. My satphone and PLB go with me every time I'm remote though, and have the advantage they can both fit in my pocket or hunting pack when on foot and away from the 4x4 too.
Jeff
1994 300TDi Defender
2010 TDV8 RRS
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