While plans for high-speed trains have slowed across the country, intercity buses are hitting the accelerator.

Florida, which rejected a $2.4 billion federal grant to launch high-speed rail service between Tampa and Orlando, is home to some of the fastest-growing bus corridors in the country.

RedCoach, a luxury bus line, increased its Florida ridership by 20 percent last year. The company's routes connect South Florida, Orlando, Gainesville and Tallahassee.

Greyhound Express this month announced an expansion of its premium service, adding service from its Atlanta hub to Jacksonville, Orlando, Tampa, Miami and Fort Lauderdale.

"The introduction of Greyhound Express to key Florida destinations now provides our customers with a comfortable and convenient premium experience along the entire East Coast, from Boston to Miami," said Dave Leach, president and CEO of Greyhound.

Though they remain cheaper than planes or trains, today's intercity express buses aren't your grandpappy's Greyhound. Featuring extra legroom and equipped with wi-fi and electrical outlets at every leather seat, the Express coaches are picking up budget-minded commuters who demand creature comforts.

Liberum Capital, an investment research firm, estimates Greyhound Express will handle 5 million passengers in 2012, up from about 4 million in 2011.

RedCoach, which bills itself as the first luxury ground transportation company in the Southeast, offers spacious cabins with about half as many seats as a standard coach.

The intercity buses are also getting easier to board. RedCoach, Greyhound and other companies are rapidly adding curbside locations so travelers do not have to haul themselves to bus stations.

DePaul University's Chaddick Institute for Metropolitan Development reported that Greyhound entered into a partnership with 7-Eleven to allow passengers to board at selected stores.

Adding to the convenience, express-bus customers can buy and print tickets online for guaranteed seating.

Unlike planes, or even trains, which can involve lengthy ground transportation, bus companies say they can get intercity travelers to their destinations faster and cheaper.

Sharon Calvert, founder of No Tax for Tracks in Hillsborough County, said luxury buses provide an efficient transportation alternative at consistently lower costs.

"A family of four could ride for the price of one bullet train ticket," she said in reference to the defunct high-speed rail project in Central Florida.

RedCoach tickets start at $30 for the Miami-West Palm Beach run. The Orlando-Miami fare costs $50. Children 7 or younger receive a 15 percent discount; 10 percent discounts apply to students, senior citizens and military personnel (active duty, reserve and retired).

Greyhound Express' online fare schedule includes $22 for its Orlando-Tampa route and $42 for Miami-Tampa.

Randal O'Toole, a senior fellow at the Washington, D.C.-based Cato Institute, said, "New-model bus companies save money by selling tickets over the Internet and loading and unloading passengers at curbsides rather than in expensive bus stations.

"They speed service by running most buses nonstop between major cities rather than making numerous intermediate stops," O'Toole stated.

Chaddick reported that curbside operators expanded daily bus service nationally by 32 percent in 2011.

Overall, intercity bus service has grown five straight years -- up a combined 34.9 percent -- while air and rail traffic has stagnated.

Still, not every bus line is a winner.

Runways Transportation last year halted its service from Jacksonville and Orlando airports (with stops in Gainesville and other cities) due to increasing gas prices and decreasing passenger travel.

But the Chaddick study found more winners than losers.