Shortly after 5 o'clock on a muggy afternoon last week, Connie Lui, spent from a long day poring over ledgers, hopped out of a powder blue Dodge van that rolled along Eighth Avenue in Sunset Park. For more than a year now, Ms. Lui has relied on the army of vans that line Eighth Avenue during rush hour to take her to and from the Chinatown meat market where she works as an accountant.

The ride costs $1.75 each way, sometimes only $1.50. To Ms. Lui, the 45-minute ride in the back of a van packed with fellow Chinese-speaking New Yorkers is far more comfortable than a longer trek on the N or R subway lines -- known among some Brooklynites as the Never and the Rarely. "The subway is dirty and dangerous," she said, shaking her head. "If we can choose, we prefer the van."

But not everybody has kind words for the estimated 100 vans that connect thousands of commuters like Ms. Lui between Chinatown and Sunset Park. Nearly a year after the City Council approved a law allowing the so-called "dollar vans" to obtain licenses to operate legally, the unlicensed, sometimes dangerous, vans that ply the streets of Sunset Park have expanded their service, opting to take passengers straight to Manhattan. In other parts of the city, vans drop riders at subway stations. Transit Authority officials were not available for comment on Friday.

Police in the 72nd Precinct, which has jurisdiction over portions of Sunset Park, say the illegal vans frequently lack insurance, seat belts and fire extinguishers. Other critics, including Councilwoman Joan Griffin McCabe, charge that during rush hour, the vans clog traffic and scoop up scarce parking spots along Eighth Avenue. And legal van operators -- only 3 among an estimated 9 or 10 in Sunset Park -- are infuriated by what they perceive to be unfair competition.

"They would like to rob our business," fumed Peter Wong, the owner of 183 Van Service, which runs six vans. "They try to lower their prices to $1, $1.50."

Paul Mak, president of the Brooklyn Chinese-American Association, defended the illegal operators. He said they cannot keep prices affordable for the neighborhood's low-income immigrants and meet the city's costly and complicated licensing requirements -- insurance alone, according to Mr. Wong, costs about $10,000 a year. "These van operators are just filling the service gap between the M.T.A. and the subway system," Mr. Mak argued.

Police in the 72d precinct have stepped up enforcement in recent months, said Police Officer Chris Dirusso, but the summonses and occasional confiscations of vans do little to clear the dollar vans from Eighth Avenue. "It's pretty much a revolving door," he said. "We do what we can."

One driver of an illegal van on Eighth Avenue who insisted on anonymity shrugged when asked about the stepped-up enforcement. On the day that the police issue tickets, said the driver through an interpreter, he stays off the road. SOMINI SENGUPTA