2degrees is currently putting up towers here, and I know of a few people who are having trouble with their 2degrees phones. She should be able to connect to Vodafone's network in the mean time though. It's also worth noting that Vodafone has terrible coverage in West Timaru, so maybe her phone is just running on a different band than yours that doesn't have as much range. The closest Vodafone tower would be near the Countdown on Church street or the one in Marchwiel.
The new LG phone is working well - on the Vodafone network, I assume. SWMBO is a bit disappointed with battery life, but she's comparing with the E62, which did very little and used very little juice to do it.