Whichever gives you the highest credit limit with promo 0% APR for the longest. There's many options who give you free money for 12-18months. Speculative attack for the poors 🤷‍♂️

Citi, Discover, Fidelity had been the most generous to me in the past.

*I got a little theory that if you tell them in the application form that you ARE planning to do a sizeable balance transfer, they will give you higher credit limit than otherwise (balance transfer fee is the instant money for them, vs just waiting for potential interest to kick in).

**don't forget to pay the minimums; and the balance when it gets due.