We are still EARLY in the stages of looking at buying, but it would be nice if we could at least narrow it down to S vs. X. Here is our situation: This would be my husband's car, used primarily for in town driving, and maybe some work trips (up to 4 hours away, typically). We have 4 kids (16, 11, and 3 year old twins). He picks the kids up from school a fair bit, so it would be nice to have the option to put all 4 kids in one car if necessary (realistically, the 16 year old will usually be driving, so it will probably be just 3 most of the time). However, it would not be the primary kid car. We figure for occasional in-town trips, the rear facing seats would work for the little ones for a few years, but is this a good solution? Would we be a lot happier with the X? Thanks!