Yep - if you don't have a TrackIR, get one. You'll never "fly" without it once you've used it.
I have a 3x24" widescreen setup using an Eyefinity card (avoid the Matrox Triplehead2Go these days as they're now obsolete effectively), and with the TrackIR it's a pretty decent simulation. I have both FSX and X-Plane.
FSX is a better "sim" for the heavies and procedural stuff and has a better software/add-on base/more available scenery.
X-Plane is better in that it has non-level runways and a different (but not necessarily more realistic) flight dynamic. The downside of X-Plane is that it's an eye-popping 100Gb install for world wide coverage and the default aircraft are of poor quality. However, the recent Carenado X-Plane releases knock spots off the FSX versions, so it's very much swings and roundabouts.
I've always been into flight sims since the days of my Apple II and ZX Spectrum - didn't find it a hinderance when I learned to fly and was never guilty of "head in the panel" syndrome.
These days, I fly purely VFR/Low level in the sim but don't equate it to the real world. It's a complementary hobby in the same vein rather than a learning/currency tool.
However, the sims are excellent for instrument practice as I'm finding with the IMC coursework.
(If anyone is bored going from A to B at random in FS and needs some structure under the guise of hauling cargo, go check out AirHauler by Just Flight
)