I've got two 09's, XT and an X.
I'm in my sixties and one thing I have learned over the years is, no two cars dive or feel exactly the same even though they might be the same year, model, and equipped the same.
I find the XT suspension rides a tad stiffer, not firmer, feels more stable to me. There is a slightly different spec on clearance between the XT and the X. The XT being something like 1/4 inch higher. The XT has less road noise, feels like it handles a bit better.
The transmission feels noticeably different between them. The X is smother shifting, stays in each gear a bit longer. XT has a firmer shift, shifts sooner.
There are other subtle differences between them I won't go into right now, but the other obvious difference for me is the XT comes with a telescoping steering column which makes it much more comfortable for me.
My wife hates leather so neither is a Limited model, I'm not sure if the Limited X includes the telescoping steering column or if it only comes on the XT.
As posted above the final gearing is a bit different between them. XT is turning less RPM's at freeway speeds.
As I'm sure you already know the X gets better gas mileage and uses regular gas. The XT drinks a bit more fuel and needs premium fuel.
The XT wins the fun factor. Honestly I like the XT a bit better but would be happy driving just the X model.
But then I have two 1969 Pontiac GTO's parked in my garage so if I feel the need to burn rubber or melt some asphalt they get the nod.