BOSTON -- A sting operation in New York over the weekend has many bus riders nervous. All 14 tour buses pulled over were ordered off the road.

It follows two separate bus crashes that killed 17 people. Some of the discount bus lines operate in Massachusetts

"The price is right, and the bus is actually nicer, and I've been taking the Greyhound and Peter Pan for eight years on this route," Worldwide passenger Anne McCauley said.

Worldwide is only the latest low-cost carrier to grab headlines. A ticket from Cambridge or Newton to Manhattan costs $15.

Last week, 15 people were killed when a bus returning from the Connecticut casinos tipped over in the Bronx and was sliced by a pole. Another discount bus crash in New Jersey killed two others two days later.

"The discount, some of them, not all of them, but some of them hold back in certain areas. They may not have a full-time fleet mechanic. They may not have a full-time safety person," transportation consultant Joe Mokrisky said.

According to the Federal Transportation Department, during the past 24 months Worldwide has only one score with an alert status. That was for driver fatigue.

This compares to Fung Wah, which five years ago made headlines with a bus fire and accidents. Today, its federal records show three alert statuses for driver fatigue, driver fitness and vehicle maintenance.

"Most of it is driver error -- not for driving conditions. A lot of drivers are not properly trained. And they get a license and they get out on the street," Mokrisky said.

There are no separate safety numbers for discount carriers Bolt and Mega Bus, which are owned by larger, established corporations.

"They have an overall culture of safety and a professional system. If they are considered discount, which they are in some cases, because they are owned by corporate partners which have an overall commitment to safety, it does trickle down to their discount business, as well," Mokrisky said.