French-born Vigneau pleaded guilty in the Wellington District Court earlier this year to selling 4-MEC, a class C controlled drug identified by Environmental Science and Research at the time as the latest designer drug, similar to ecstasy.
He also admitted selling cannabis and being in possession of an LSD tab when police searched him on August 25 this year.
A district court judge declined to sentence Vigneau, saying there was a real possibility the High Court would impose a harsher penalty.
Lawyer Keith Jefferies told Justice Jillian Mallon today that Vigneau had been in employment but trying to start his own business. The drug dealing was "aberrant behaviour, given his background'' and initially began so that he could pay his rent.
Crown prosecutor Ian Murray said the dealing had gone on for a year, until police brought it to an end. A significant amount of drugs had been "introduced to the community'' for Vigneau's personal gain.
Police had estimated his income from drugs at $520,000, based on a 12-month collection of tick lists and documentation found when they raided his Hataitai home.
However, a disputed facts hearing resulted in Justice Mallon reducing that amount substantially. But, she said, Vigneau was more than an occasional dealer. His turnover was regular "and not insubstantial.''
Sometimes netting $3000 on a single occasion, he often sold pills for particular events - up to 40 or 50 designer tablets for a party of about 100 people.
She said he had lived in New Zealand for a number of years but had spent periods in France and Australia.
According to pre-sentence reports, Vigneau was in a two-year relationship, had several close friends and many good qualities. He had acknowledged previously using alcohol to excess and taking various drugs for a number of years - although he did not believe he had a drug problem.
Police nabbed Vigneau after tracking him down from mobile phone records when the drugs package sent from Blenheim was opened. He had made telephone calls to the courier company inquiring about the non-arrival of a parcel he was expecting.
A regular traveller between Wellington and Marlborough, Vigneau was arrested in August when he flew into Wellington Airport.