I don't have Alesis pads, but I have similar reflection-plate style drums. I got them in 1995, they came with typical black mylar heads, and I wasn't aware for the longest time that putting mesh heads on them was an option. After reading about it, I tried out a Pearl mesh head (cheap) and it worked. The difference in ambient noise (stick noise in the room) was so huge that I ended up upgrading the whole kit, and now I play them a lot. The stick noise was always an annoying issue with mylar ("real") heads. Now I have Hart mesh heads (Maxxum on snare, Magnums on toms) and they are great.
I doubt you'll be disappointed going from mylar to any brand of mesh. Just about everyone who makes the switch is thrilled.