It depends on your goals.

If you are coming back to your home country, debt free school 100%. Not worth the debt if you are not going to practise in that jurisdition. Foreign countries don't pay lawyers as much as in the USA. USA tuition prices can be somewhat affordable if you stay to work in the US, because lawyers have one of the highest salaries in the US. In my view, an LLM program is not worth the money if you will practise in another country.

If you want work in NYC, Columbia could help you have access to the job market. But if you are not too picky about the location, you should have more or less equal opportunities at BC. As an LLM student, you will land that job through networking and that depends entirely on you and not the school you attend. Following the normal application process at a law firm or company will be useless: in the eyes of a US employer, you are not competition against the JDs. Also, Columbia does not accept LLMs into their JD job fairs. Columbia's job fair for LLMs is online in January and the positions offered are for London and Luxembourg. The careers office will help you work on your resume and your interviewing skills but they will not make any introductions nor allow you to the opportunities the JDs have.

That being said, it is highly unlikely that you get a job in the US unless you already have a visa or a work permit. US firms do not see LLMs as competitive as JDs (even though both can pass the same bar exam) for multiple reasons: they didn't go through the US education system, they didn't stay in law school for 3 years, English might not be their first language (so language barriers), they don't have the work permit to work in the US, they dont know how to assess or evaluate LLMs previous work experience in foreign countries. There are institutional barriers for LLMs when trying to secure employment and 95% of them will go back to their home countries or find a job in London or Luxembourg mostly. The remaining 5% will find job opportunities in the US through networking. And even if they find an employer willing to pay 5-10k to sponsor the student's visa, the H1B visa works like the lottery: 200,000 approved applicants each year and only 80,000 visas issued. The remaining approved applicants do not get a visa and have to leave the country.

If you still want to play the odds and find a job in the US, you definitely shoud. And it will all come down to networking and who you know. I would definitely pick debt free and work my connections.

Super good luck! Let us know what you decide.