or...should i try and find the hardrock pro disk which will run me no more than $150 difference in price but for that price i get

-shimano deore derailers
-avid bb5 brakes

is it worth it to just spend a little more now instead of upgrading to the avid brakes or deore derailer after or should i just stick with the comp disk, i have been reading that the avids are really nice and that to get them on your bike after the fact would add up to at least $250-300 for the brakes and wheels or whatever, gonna test ride it today or tomorrow