Modified battery holders
I ordered a set of the carbon fiber battery holders and decided to modify them a bit to make them work better. They are designed to sit flat on the chassis and have the plastic hold down put on top, unfortunately this covers (almost entirely) the grooved slots in the chassis for taping. You can tape on top of the chassis still, but still wanted to tap under if I wanted. It's optional I ground the holders a bit to fit better (thinner and one edge shorter to not rub the steering mechanism). Works really good so far and holds the battery in much better.
I've been racing associated cars for a long time and can say that the 411 is a great quality car and very fast on carpet with minor adjustments.