Who cares if you get a car allowance? That has nothing to do with this job been great (or awful depending on who you talk with). What are you concerned that you might not get a leased camry, or fusion for "free"? Is that $400 a month perk enough to make you lose sleep at night? You get an allowance. Regardless, if you a making 175-230 it doesn't matter you can get your own damn car. You can even be the assclown that roles up in a Range if you want.
These type of questions are awful and always repeated on every board.
Do you know or have you ever even met a ISI rep in your area? Ask them. Do you see them pull up in a Prius or a Yukon? Wait? What's that? Oh that right, no one cares.