X is the base model. I don't have my copy of the brochure with me, but in 06 that meant it had roll up windows etc. You could get it in 4 wheel drive, but did not have descent control or locking rear differential if I remember correctly. Everything was optional that you would probably want. I looked at and X when I bought mine, but decided on the OR because with rebates and discounts it was going to be cheaper in the long run to bite the bullet.