HiI am thinking of getting the trackir-but can't seem to decide betweenthe model 3 and 4.I can get the trackir 3 from ebay for about

IR4 has the 6DOM built in, that is an add-on cost for IR3.Without 6DOM, TrackIR is not worth it.The 3 + add-on is still cheaper then 4, but for the smaller size and greater view angle, it is worth it.* Orest

I had Track IR3 plus Vector expansion. Then I bought Track IR4.In Use, I cannot tel any difference between the two. Although Track IR v4 suppose to have higher resolution , In reality , I can't tell the diference.So V.3 + Vector Expansion = V 4V4 is smaller is size.If you already have v3+VE then it is not worth getting V4. If you don't have any, the get V4.

I dont know how I lived so long without it(IR4).....I would say to anyone who still doesnt have it what are you waiting for?....Flight sim will never be the same.Ruben Romero"FS9 THE LAST TRUE SIM"