I'm sure there are many opinion on this situation...
I recently accepted a job offer at company B, about a week ago. I went to resign at company A and they countered. At company A my role is currently ending, and company A says they have plans to transition me into another project. I knew about this, however I needed a change immediately and decided to accept another job offer. Well, when I tried to put in my two weeks, they countered with the same transition plan this time faster and with more money and a career plan. Given the hideous amount of student loans I have I decided this is a much better offer, and I would like to stay. I requested they put it in a contract, and I am still waiting on the contract a week after I accepted an offer from company B.
Now I feel horrible for company B because I may be rescinding my acceptance about a week before my start date. Is it unprofessional to rescind a job offer acceptance?