break in 1k miles vs 500

im picking up my sti in a few weeks and am wondering about the break in period. Where does the 1k mile break in come from, ive always heard 500. Im def going to do the 1k break in i would just like to know.

another thing is that i will be driving it from the dealers lot to my house which is 500 miles away. I want to take it home that same day but would it be better for the engine if i drove a few hundred miles then stayed the night in a hotel and drive the rest the next day.

also it will be highway most of the way so going 60 or 65 for 400 -500 miles. Is this to quick of a break in

thanks