I like the look of that Serpent. I drove a serpent at the IIC and it was always easy and responded well to changes. I think I may pass this Xti off to a guy at my track who wants to get started in 1/12 and just keep the XL and Serpent... but I will probably prove to be too lazy.
I measured the difference in pod length from the XL to the Xti and its nearly 0.2", or roughly 10% of the total pod length. The Xti main chassis is close to a half inch longer from the front axle to the pod, giving it an overall longer wheelbase. XL and Xti both double-steered like a bitch with the stock setup, but radical shock changes fixed that.