I've now bought what I was told was Rotala mini type 1 twice, only to have type 2 show up.
I thought this a might be helpful for folks to understand the size difference between them. Type 1 is maybe 1/8" all the way across. Type 2 is almost as big as Ammania Bonsai, maybe 3/8" across.
Type 1 leaves curl under from end to end, but do not curl up side to side. In a dosed tank, Type 2 leaves curl up side to side.
Here is a picture of the two right next to each other. Type 1 in the center, Type 2 on either side of it. Those are the leaves of Java Fern Trident behind it, and an undescribed dwarf lillaeopsis in front of it the size of (chubby leaved) hairgrass for reference to sizes.