The x brace worked well, but had about 4 inches or so behind the tranny plate yet in front of the rear axle that had a little flex. It wasn't bad until I noticed the frame start cracking in that area. My "3rd gen" frame is now boxed front to back. It seems to be the most consistent as far as driving into the corner and most responsive to a chassis tune and tweak than the earlier versions of this chassis I have built.