Those diff kit's are great value for the money. If the gears in your stock diff are in good condition, just get that kit and transfer the gears from stock diff to the new adj diff.

About raising or not, i just heard allot of people having troubles when raising their diff's, problems with gears slipping or something. I dont know if it is solved yet, but either raising it or doing it the way i did... there you have two way you can go