I originally thought that CI extensions were important, but I bought the Delta 36-675 when it went on clearance a few years ago because I could not beat the price. The 36-675 has two stamped steel wings, but is otherwise pretty close to the new 36-979 (which has 2 CI wings, built-in mobile base, and built-in dust collection port as the main differences I saw). Both have the T2 fence, which I like a lot.

I have to say that I now feel that CI extensions are not terribly important, at least to me. Horsepower (2hp would be nice, but 1.5 hp has been good enough for everything I need with a good thin kerf blade) and a good fence for a good price are the main features that I would look for. If it's a well known name brand, the rest of the features are probably going to be suitable for what you want to do.

Further, for any contractor saw, I would recommend getting a link belt to reduce vibration and (as for any saw) a good blade (Leitz, Forrest WWII, Freud LU-84). Whatever your budget is, knock $100 off and buy these two items with that $100, and get Jim Tolpin's Tablesaw Magic.

If my choice was between getting the blade and link belt or the extra CI wings, the blade and link belt would win out every time. At 300+ lbs, my saw with stamped wings isn't going anywhere, and it still passes the nickel test. I have since had the opportunity to add CI extensions, but felt the money would be better spent elsewhere.