If the $16/19 suits our needs are there really a difference between the companies? 

Skinny is $3 less, maybe on a better coverage network?  Vodafone is still ok.  Telecom ditto but no carry over units.  2Degrees seems to not have as a good coverage area - it's probably great for where most people work and live but if one gets to the fringe areas they don't have roaming agreements everywhere.  Ie in Wellington, Owhiro Bay or Makara you get a signal with Vodafone but you just don't get a or much a signal with 2Degrees. 

Thanks.