Thanks for your replies.

I've taken the phone into Telecom as I'm mindful that it's just about to cross the two year warranty boundary (CGA aside.)

At the end of the day, 2 weeks without the phone (the loaner is a shocker...) while the handset gets "investigated" is a hassle and it does put me in the position of refreshing the apps loaded/personal configuration. 

Might be time to upgrade. 

Is it worth while waiting for Wellington-based 4G coverage and a reasonable handset choice or do I just upgrade to a HSPA+ handset in the shorter term?