[EricH]

Originally Posted by Bochek

Team 2200 has been 100% student built to date, and we are doing just great.

Not only that but our team consists of 12 programmers and 2 people with knowledge on actually machining and physically building the robot.
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Its nice to know that you built it. and that you know that it will work for sure

As has been said before, if you used anything (controller, gearbox, motor, etc.) from the KOP, you aren't 100% student built. Engineers built the items in the kit.

That said, have you tested your design yet? I think you'd hate to get to your first regional and find out that the robot doesn't work, forcing you to call for reinforcements from the other teams. (And I bet that some of those extra hands will belong to engineers.) Test it now, rebuild it now, and find out why it failed if it fails.

If nothing else, you should have one engineer to figure out where you screw up when you do something wrong. An illustration: I mentored a Lego League team two years ago. The students were all rookies. The robot had trouble coming away from one mission. I looked at the "code" they had carefully and, lo and behold, I found out why they weren't consistent coming out. They'd put a right turn in with the left wheel forward instead of the right wheel backward, causing them to jam into the field element they were trying to work with. I showed them how to fix it (or how I fixed it, I forget which) and told them to consider it a learning experience. This is what the mentors are for--preventing or fixing student errors that cost the team time or money.

100% student built is not necessarily a good thing. 95% student built means that you have a mentor who will help you to do better.