The S101 is Asustek’s high-end netbook/ultraportable, with a much larger capacity battery, and more metal parts (which adds to the price), while the 1002HA has a higher-resolution webcam. As shown, they do have the same keyboards and the S101H and 1002HA share quite a few other things in common.
PM makes the point that the S101H is just the S101 with a hard drive (the S101 has a Solid State Drive – SSD), and at that point the S101H is:
… actually half way between the S101 and the 1002HA. The differences are all so minimal though and donâ€™t amount to much. I would either stick to the 1002HA and save money, or go for complete mobility and battery life with the S101.
Portable Monkey makes a great argument for picking up the 1002HA over the S101H, since the whole point of choosing the S101H is for the mobility and battery life.
Read: Portable Monkey