I always go with big bearing housings and axles if the car has a decent amount of HP. The small bearing axles, regardless of spline count, are no bigger than a regular 8" axle. Most axles always break at the bearing, not the splines. Also, the small bearing housings are light duty, and the housing will distort where the spring perches weld to the housing. I avoid small bearing housings and axles like the plague, as they don't belong on a high HP car.