The Paxster, dubbed "Polly" by staff, could carry 10 times the weight of a bicycle, and the Kyburz, or "Kip", could carry five times the weight.
But posties would still remain a regular sight.
"Regardless of what's decided they will complement rather than replace walking, cycling and vans," Trow said.
"As we carry more parcels in our network it makes sense to look at using different types of vehicles that are smaller than a van, but carry more than a bicycle."
Trow said the trial, which ended last month, would also assess their suitability for the terrain and impact on roads and footpaths.
This would help Auckland Transport determine whether to approve the use of the vehicles on city footpaths.
NZ Post was also trialling an e-bike in the West Auckland suburb of New Lynn.
The power-assisted bike could reach up to 40km/h and rolled to a stop when the postie stopped pedalling.
NZ Post recommended a top speed of 10km/h on the footpath.
The vehicles were expected to give way to pedestrians and other vehicles, including mobility scooters.
Earlier trials in Wellington found the vehicles were safe and efficient causing no damage to footpaths apart from normal wear and tear. The same vehicles were used extensively by European postal authorities.