回复：NIW recommendation letter form

It is difficult to say one is better than the other. You can use both formats to draft your reference letters. Your reference letters should give immigration officer a picture that your work is in national interest and you are superior to your peers (including foreigners and Americans) in your area. Your work can not be done by an American person who meets the minimum requirements by labor certificate.
Your previous achievements are the clear evidence to show that you will do better than your peers in the future in terms of national interest. Good luck.