i'll tell you a little secret,
you can buy a behringer MDX2400 for about $45 on ebay, take off the cover, replace the caps with elna's or whatever, replace the 4 X behringer chips with 2 X dual OPA2134 surfacemount with adapters from browndog on a new socket , they are plug and play, replace the crappy noisy 15v 7815 regulators with 18V superregulators (i found a few on ebay that fit prefectly) and you'll have 4 very very good feedforward compressor limiters, for about $200 if thats cheap enough for you
you'll need the germany build MDX2400 , they are 1:1 copy's of DBX with the DBX1252 VCA and DBX1253 detector in it (they are known to be good) , i cant remember what type they copied exactly , i think i read somewhere it was the 160XT.
peace