Hi, I would say that it depends on the reason for which the applicant was refused.
You must keep in mind that CIC Officers have a level of knowledge and expertise, they've seen a lot. If for example they believe that you're not able to establish yourself in Canada, perhaps you're lacking something (education, work experience, language skills, etc.) so is it really worth fitting this at court which can be costly and stressful?
....in a case like this, I would rather improve my skills and re-apply in the future. The gov. will give you the option for an appeal but that doesn't mean that everyone must appeal.