This.

I just bought a set of Conti 4 Seasons for my commuter, and I'm just smitten with them. They're the most fun to ride on of any tire this side of a full on racing slick. Conti claims the 700x28 folding model weighs just 250 grams. It feels like it.

That said, to answer your actual question, you definitely will feel the difference between the SMPs and the Gators. I haven't used the Hardshells. I have used the regular Gatorskins. They roll nicely, but I found that the flat protection is decreased after about 2000 miles (I expect that to be true of the 4 Seasons too, FWIW.) I also fully expect the SMPs are more puncture resistant than the Gators, but it's the difference between excellent and amazing.

Ultimately, you need to decide how much the feel of the ride is worth to you versus flat avoidance and durability.