The bottom line is that you don't know how well you'll do on the MCAT until that score report comes in the mail. There are those that have scored mediocre scores on Kaplan and gone on to do very well on the MCAT, and there are also those that went in with "30+" practice scores and got mid-20s. Being confident in your abilites is nice, and feeling like you're "good at what the MCAT tests" is nice, but remember that the MCAT is more a thinking test than a topical. It's simply useless to speculate upon a hypothetical future in which you've scored your ideal MCAT, because hardly any of us have done that (with the exception of a few!).
Now, that being said, I will tell you that whatever rumor is spreading around here that Osteopathic schools don't care that much about your MCAT score is FALSE. If you're expecting DO programs to simply roll over and let you in based on what you perceive to be your own merit, then you're sadly mistaken. Every year there are stellar candidates who are turned away from DO programs. If getting in to a DO program is so easy, then why did my school have 4,000 primary applications for 100 spots? 4% getting in is not what I'd call "easy entrance into DO school".
Like all medical schools in the US, there are many EQUALLY-WEIGHTED factors and some that are MORE HEAVILY weighted that go into the selection of a good candidate. The five biggies are:
1)MCAT score
2)Science and cumulative GPA
3)Extracurriculars(including research, volunteering, shadowing, etc.)
4)Interview
5)Letters of Recommendation.
Yes, DO schools do tend to pay a little more attention to extracurriculars, but only because they like to foster an eclectic, well-rounded applicant. They are not after the gunners and trolls; there are plenty of MD programs that would LOVE to have them. However, they believe that what extracurriculars an individual has chosen to donate their time to says a lot about the person. For example, if they volunteered in an ER(EVERYONE does this), were a member of the premed honor society(EVERYONE does this), and did research on campus(EVERYONE does this), then they've done nothing special in the eyes of the committee. However, if (for example) they've spent significant time abroad, volunteering their time, gaining a cultural perspective, then they've done something that hardly anyone does, and that makes the individual and therefore the applicant a more interesting human being and sets them apart from the literally tens of thousands of premed hopefuls out there.
Mostly they're looking for extraordinary people, and this applies to both MD and DO programs. If you've done extensive research and are published, then you're clearly an exceptional researcher. If you've managed to keep a 4.0 and have a 35+ MCAT, then you've either not had to work full time through undergraduate or you are a very dedicated student. If you have a list of extracurriculars that takes up a lot of disc space, then you're probably a very dedicated humanitarian. All of these people listed above are EXCEPTIONAL and extraordinary individuals. These are the types of people that schools are looking for. Because medicine is a primarily humanistic endeavor, they are looking for a humanistically diverse set of future physicians. Whom they choose is up to them, but you should go into this process knowing that there's a lot more to it than your "expected" MCAT score. You'll be going up against people who have experienced, seen, done, accomplished more than you have, and you'll have to have something more to offer the committee than "I THOUGHT I was going to rock the MCAT". Good luck to you.