Foxy, you can go about this in several different ways...........
First off, if you've never fired a SxS, I would encourage you to do so before you make a purchase. SxS guns are cool. No doubt. But there are several drawbacks. Some of them have "torque" when fired. That is, they try to twist a little due to the barrels being off the centerline of the action. Some people can't deal with it ... some can. I LOVE shooting my CZ, but my son hates it. Different strokes, I suppose. Also, expect a SxS to be much lighter and have more felt recoil.
You say that an O/U doesn't interest you, but if I had my pic of a 2-tube gun to use, the choice would be the O/U. Less felt recoil because the barrels are more in line with the buttstock rather than above it, and the sighting plane is easier for me personally to pick up. Of course, all of these things are subject to each individual's personal tastes.
The guns "of choice" would definitely be Browning or Beretta if going with the O/U, but the CZ is also a great little gun. The Stoegers are proving to be "so-so" after extended use (I'm sure I'll get some backlash from that statement). If you are going to use this gun for field use only (less than 5000 rounds per year), don't overlook the Yildiz at Academy Sports. They're great little field guns and are proving themselves to be very dependable in the long run.
Take your time, handle as many as possible (unlike women, fondling GUNS is free
), and pick the one that feels best in your hands. Then decide if you can afford it. (On second thought ... these rules apply to women also
)