I’ve always looked on credit card “convenience checks” with suspicion. It’s a scam: they loan the mark money with predatory advertisements like “take that vacation you could never afford”, then charge them 19.9% interest to pay the loan off.

First USA just sent me an offer to write a check for over $15,000 at 4% fixed APR for the life of the balance. There are a few catches, but they aren’t terrible:

• 3% of the value of the check is charged as a fee, but it’s capped at $50.
• If I screw up a payment in any way, including if I “pay another creditor late”, I lose the good rate.
• Any payments I make on the card first go to this loan, and only later go to pay off normal charges that bear a higher interest rate

I’ve never been in debt to a credit card company and don’t have any need to start now. Still, $15,000 at 4% with no collateral and no payment term is a pretty good deal.