I have done some more digging and a YouTuber responded with:
"The receiver always needs battery. It's only a power off feature to help conserve battery. If no phantom, the it powers down. It will always need battery power."
So that clears that up :)
I opted for the AVX ME2 system. They arrived yesterday and the ease of use is just a dream to be honest. Far more compact than the Rode Link and about 10 times better in build quality. I'm yet to properly test the audio. I love that you can just plug directly into your XLR and that you don't need to fiddle about with the transmitter once you have your talent wired up. So far, so good...
Oh and no AA batteries, just USB charge. Perfect.
I think the AVX-ME2 may be my answer!
The way I see it is Rode Link:
pros: digital, cheap, good reputation
cons: chunky, have heard dodgy things
G3: Pretty much industry standard, good rep, proven reliability
Cons: Not digital so susceptible to inteference, double the price
When you say served you well, what do you mean? For how long? How often have you encountered interference issues? If you were buying your next set, what brand would you buy?
Appreciate your response :)