Ha'apai Mobile Coverage?

Which provider has the best coverage across Ha'apai and what does that mean in practice? Good coverage from Ha'ano to 'Uiha?

I'm thinking of getting a Visitors Pack and using a cheap handset rather than roaming with my normal mobile.

Here are the main providers I think:

[http://www.tonfon.to/mobile-services.html]
[http://www.tcc.to/index.php/2009/06/09/ucall-prepaid/]

Thanks

Tonfon don't exist any more, they were replaced with Digicel.

I'll answer my own post after visiting Ha'apai Oct/Nov.

Bought a TCC SIM in Nuku'alofa with $T5 for $T25. Re-charge cards widely available.

Excellent coverage in Ha'apai on Lifuka and Uoleva.

Cheap local and international calls compared to NZ.

The only problems were one day when the network apparently crashed for part of the day and problems txting UK and NZ Telecom mobiles. No problems txting NZ Vodafone.