I suspect that the division of opinion pretty much breaks down along two lines of thinking. If what you are after from the performance is some semblance of historical accuracy/authenticity, then perhaps Quaid's portrayal is the one you favor. If, on the other hand, what you prefer is a superlative, sparkling, Oscar-worthy theatrical star-turn, then you doubtless appreciate Kilmer's interpretation of the character. On the other hand, there is no law that says one cannot like both of them, if not equally, then at least for what the respective portrayals offer each in their own way. Personally, I appreciated the one, while enjoying the other. There is this though, that while one of the films in which the character is depicted is eminently watchable, the other is, perhaps, less so.