You ought to be fine driving on those axles, but that's up to you.
Anyway, yeah, vxs do take a beating on gas mileage, this was one of the reasons I was telling you 50mpg in a del sol wasn't exactly common,
I'd monitor the signal of the o2 sensor a bit when you get it to see how it's running, if it's getting lazy or just giving bad signals or what, *shrug*
Time will tell.
__________________