Earlier this year, his 14-mile slog home took 50 minutes out of his day, if there weren't any accidents. "It was murder," he said.
But his evening commute recently got a whole lot better - for a price. Drivers like him can pay anywhere from 25 cents to $6.20 to drive in a new express lane for six miles at or above 45 to 50 mph, guaranteed.
Now Kubiliun gets home in 20 minutes.
"That thing's a godsend," he said. "I can even make it to my kid's baseball practice."
These High Occupancy Toll lanes - or HOT lanes - are praised by urban planners, environmentalists and many drivers. From I-10 in Houston to I-15 in Salt Lake City, drivers can pay extra to zip past traffic stuck in the slower "local" lanes. HOT lanes also are being added in northern Virginia.
They've been criticized by some as "Lexus Lanes" because of the cost, but in Miami and other cities, it's not just the drivers with fat wallets who can use them: Carpoolers, motorcyclists, buses and hybrid owners drive for free.
"It's one of several huge trends in urban highway transportation," said Tyler Duvall, acting undersecretary of policy for the U.S. Department of Transportation. "You're seeing at least 10 major metro areas with HOT lanes or HOT lane projects. If you're a major city and you've experienced congestion, you either have a HOT lane or you're going to have one in five years."
But do they reduce congestion? HOT lanes haven't been around long enough for researchers to say. Some speculate they could add to congestion by encouraging drivers who can afford to pay the tolls to live in far-flung suburbs.
But many experts say the option of paying for a quicker commute should be available and the proceeds can go toward improving public transportation or roads.
"In the future, congestion pricing is going to be the way we get around in this country," said Gabriel Bernal-Lopez of Miami, a transportation engineering student at the University of Florida and the founder of transitmiami.com, a widely read blog in South Florida. "It's about time that motorists pay their fair share, and HOT lanes are a step in the right direction."
HOT lanes began - like many traffic trends do - in congested Southern California in the mid-1990s. By 2006, they were in place in Texas, Minnesota and Colorado, and the planning of South Florida's $122 million I-95 project was under way.
Federal and state officials are big proponents of HOT lanes, largely because they cost less and require neither new asphalt nor the lengthy approval process for building or expanding new highways.
But groups like the AAA are a bit skeptical.
"AAA believes that all roads should be toll-free. Where toll roads are utilized, reasonable alternative toll-free routes should always be available," said Gregg Laskoski, spokesman for AAA South. HOT lanes are only appropriate if an existing car pool lane is underutilized and the change won't contribute to congestion, he said.
That's exactly the situation in Miami. The six-mile HOT lane was already in place as an underused lane for cars with two or more passengers.
I-95 in South Florida is notoriously congested, with 230,000-plus motorists using the highway on a typical weekday. Because of dense urban development and little available cash, expansion was not an option.
So the state began narrowing its lanes and launched a public-awareness campaign for the HOT lane, including how to get a remote transponder that automatically pays the toll as cars pass toll gates.
The project hit a snag in June, when engineers first placed flexible sticks to divide the HOT lane from the regular highway; people were caught off guard and a few motorists darted in between the dividing sticks, causing extensive backups and headaches for commuters. At least one rollover injury crash was reported.
But six months later, when drivers began to pay, there were no crashes, no road rage incidents, no problems. The tolls ranged from 25 cents to $1.75 on that first day, varying by the amount of congestion.
Officials expect to break ground on another HOT lane in the southbound stretch of I-95 in Miami soon.
Still, just because the lanes will get a motorist to his destination faster, it doesn't mean people will actually use them.
"I would rather wait an extra 15 minutes and sit in traffic than pay," he said.
For attorney Kubiliun, who has never paid more than $2 to go northbound, the southbound lane will allow him to reclaim another half-hour from the maw of traffic.
"I would pay if it was $6. I would even pay up to $10," he said. "When you do a cost-benefit analysis, with gas and the amount of time sitting in traffic, it's worth it."