Yeah i guess if i have rapport or have any idea who's looking, but I usually just assume it's going to a slush reader first. I generally do a "Hi, I'm so and so. I do x y and z.This is my piece [piece], it's an unpublished XXXX word [genre]. Thank you so much for your time and consideration."
If im a fan of the mag or very familiar with it i usually mention that as well