Depends on the brand and what spindle they're designed for...
There's some really cheap stock-car ones that the dirt-track modifieds run that are built for the sole purpose of being cheap, that I wouldn't run on a street car.
If they're designed for stock spindles, then they're too long to use with tall spindles. The only benefit to be had by running them is additional caster that's not possible with stock arms.
If they're designed for tall spindles, then there's the question of which tall spindle... B-body spindles have more KPI (King Pin Inclination... fancy way of saying the upper balljoint is further inboard), so the arms need to be short. If they're designed for any other version of a tall spindle, they need to be a little longer than the B-body conversion arms, but not as long as a stock spindle arm...
I'd recommend these for $319 as the best value for the price... only downside is that you need to trim the bracket on the frame.
http://www.scandc.com/spcarms.htm