Hi,
Writing recommendations takes a significant amount of time. No, let me restate that, writing someone a GREAT recommendation takes a significant amount of time. The Admissions Committees recognize that. They also recognize that it is likely you are asking some fairly busy people (people who are senior) to write recs, and that they are likely being asked by more than one person to do this for more than one school.
Therefore, they tend to be understanding if the recommender provides a letter rather than following their format PROVIDED that the letter answers each question they've asked, to the level of detail that they have asked it. Now, the problem is that because the questions tend to vary from school to school, it is unlikely that the letter will answer all the questions to the degree asked. That being said, I know many candidates who were admitted even though the rec was in the form of a more general letter.
As an applicant, there are many things you can do to streamline this process for your recommender and make it as pain-free as possible. Put together a packet of info for them: your resume, outline of your extracurricular activities and interests, summarize things you've worked on together, do a self-assessment where you assess your own strengths and weaknesses, and outline your career goals and why you want an MBA. Meet with them to discuss and go over it. Give them PLENTY of advance notice to work on this (2-3 months is desirable). Remind them politely of upcoming deadlines. And at the end, send them a small token of your appreciation. They will appreciate it, trust me.
As far as the number of people to ask, if have strong people you can ask, then by all means, spread the love a little bit. However, if you do not, you're better off asking the same people to do all of them as they will give you higher quality recs. Just remember to follow the process above and make it easy for them!
Good luck,
