Yeah the X2 transponder is the new version. The stopped manufacturing the 260s. The new ones are cheaper, but they get you with the subscription fee each year. Sounds like the new subscription ones are just to make more money off you, but I believe there is an online profile as well that shows your times and such if the track is using the myLaps system.

I've got a noob question as well. Do you all camp out at the track over the weekend? Also, is it a bad idea to plan on arriving Saturday morning?