NEW YORK -- A free vacation could be in the cards.Banks are competing fiercely for new credit card users, especially those with good credit. To entice new customers, several major banks are throwing in enough frequent-flier miles for two free tickets anywhere in the U.S.Charge the groceries, a night out at a restaurant and the kids' new spring outfits, and you might even earn enough rewards to also get a free hotel or car rental.Which card suits you? The first thing to do is start with a travel goal, says Gary Leff, who has been giving advice about free travel and credit cards since 2002 on his blog View from the Wing. See which airlines fly to the city you want to visit. If, for example, Southwest is the only airline, get its card.The other option is to get a credit card with flexible points that can be transferred to several airlines.American Express Membership Reward points can be transferred to 15 airline and five hotel partners. Chase Ultimate Rewards can be transferred by cardholders to four airline and three hotel partners. The most flexible transfer option, however, might be through Starwood hotels and its American Express card. The company, which includes the Sheraton and Westin chains, allows points to be transferred to 29 airline partners.Several banks are offering bonuses of 25,000 to 50,000 miles for spending anywhere from $1,000 to $5,000 in the first few months of having a card. Domestic coach tickets start at 25,000 miles, while tickets to Europe are usually 60,000 miles. Business class tickets generally require twice as many miles.Miles or cash? Airlines limit the number of seats available to travelers using miles. During holidays and other peak travel periods, there might not be any seats open for mileage redemption.In some cases, miles aren't even the best option. If you want to fly domestically in coach, the best bet isn't an airline card but one offering cash back. (Those looking for international business class seats should still stick to miles.)Fidelity has an American Express card that gives a 2 percent rebate. Priceline has a Visa that offers 2 percent cash back, which can be used to pay your credit card bill.With airline cards typically offering one mile for every dollar charged, it would take $25,000 to earn enough miles for a free flight. With a 2 percent cash back card, that same amount of spending would earn a $500 rebate, enough to purchase most domestic flights and without any of the hassles of trying to redeem miles. "Cash trumps free anything because you can do anything with it," says Tim Winship, publisher of FrequentFlier.com, an advice site for travelers.So instead of saving miles for that dream Hawaiian vacation, just get enough cash back to pay for it yourself.Is loyalty worth it? Winship says there has been a gradual erosion of the value of these miles and award ticket availability is getting harder to find."I'm not saying loyalty programs are worthless. I'm saying they are worth less today than they were five years ago and will be worth less in five years," Winship says.Many of the hotel and airline cards also come with hefty annual fees, typically ranging from $50 to $100 but sometimes as high as $450. Those fees are worth paying only if you are charging a few thousand dollars each month.There is one exception: Some hotel cards, such as the ones for Hyatt, Marriott and InterContinental Hotels -- which includes Holiday Inn -- come with a free night at certain level hotels each year. The cost of the annual fee is often less than one night's hotel bill.