2.
BenQ XL2420T. I don't own this one myself, but I've heard nothing but good things about it. 24", 120Hz. From what I can remember it's a bit heavier and more adjustable. I've seen this go for quite a bit higher price than the first one I mentioned, but not in this case.
As for 3D - personal preference. I have absolutely no interest in 3D at all, and from what I've heard gaming with 3D is not exactly
ideal.
By the way, my S23A700D came with 3D glasses. Not sure how that is with the XL2420T.