I am new to the site, but I was under the assumption this was about law schools. Are you planning on going to law school no matter which program you choose?
If you are planning on law school, I would probably do the MBA, so long as it will satisfy your state's (NY?) requirements for the CPA exam. That's what I did and took the CPA the summer after I graduated and started law school after working for a year in public accounting. I believe it helped me get into the law school I wanted to go to, and the CPA definitely helped me land my internships (currently a 2L).
If you do not plan on going to law school, getting your CPA is the best thing you can do for your accounting career, regardless of what type of accounting work you want to do. If you can get the kind of job you want by doing the 3+2 program, I would do that. If not, then you should start looking at other options.
Hope rhis helps and sorry if there are typos. I'm on my phone watching basketball.