N0P1st0ns

Came across some rims I liked but with 9.5 the highest offset would leave me poking a bit. so i moved on. Found a desired offset with 8.5 that would fit nicely. This aside, my question is simply what is everyones thoughts on these widths? what is the difference? What do you guys prefer? I noticed most people go with 9.5. Is that for a specific reason? just enlighten me. why 8.5? why 9.5? Thanks guys.