[dubious elise]

For the past two years, we have built a competition robot and a practice robot almost simultaneously. This is primarily becase we have been using steel for frames and could only get a mentor or parent to come in once in a great long while to weld everything perfectly square for us. Our practice bot is usually at least a few steps ahead of our competition bot so that we can work out all of the kinks before we make a big decision.
Practice bots are also great for getting the feel of driving with whatever drivetrain you are using for the year before you have to ship off the final bot.