A 1" diff drop only drops the front, so essentially you are just rolling the diff down. This results in less than 1/2" of movement where the CVs enter the diff. Like you mentioned, it also changes the DS angle, which may not be an issue, but it could. From all that I've read, most people that have an option on diff drops, have a negative opinion. It may not cause problems, but in the 2.5-3" lift range it's probably not necessary.
