so my driveshaft is F'ed

i need a new one so i'm going to go ahead and get one made (w/ greasable u-joints)

i got a rough estimate (over the phone without any real information about leangth and so on) of $600 is that good/ bad? (i was quoted approx 600+ to replace the stock one)

also does anyone here run a custom driveshaft?
pros/cons?

thanks