Personally, I have never understood the appeal of Alcantara. Strikes me as the kind of thing that will be tough to keep looking clean, especially on something that will have a lot of folds.
If you were going to buy a new jacket would it be leather or suede? I have both and suede starts to look grungy pretty quickly. Now I like Alcantara, have it in my GT/CS. But leather is easier to maintain so pick you poison. They will both look great, a least to start.