Without a doubt the API 560, but I could easily live with an API 550 or a Massive Passive or Great River eq...

The 560 certainly does rule! We have a pair across our mix bus.
You might look at something different, though. I recently got an
Earthworks "Kickpad"...it certainly lives up to its claim that it will convert ANY mic (well, maybe not a Green Bullet) into a great kick drum mic...$100.00. It has certainly given my old EV's a new reason to live!

Most of the time I don't use a ton of EQ, usually just to high or low pass, but sometimes kick drum can benefit from attenuating the low midrange.

Below is what I use in our mix room (in addition to the very occasional plug in for special effects and also board EQ), this is per channel, not per unit.

They all work fine for kick drum, but the most flexible are the ones with the ability to vary the Q, and with sweepable frequency selection, such as the Buzz MPE, Great River, or Crane Song.

(2) API 550b EQ
(1) Buzz Audio ARC 1.1 EQ (Channel)
(2) Buzz Audio MPE1.1 ST
(2) Crane Song IBIS Mastering EQ
(2) Chandler TG-Channel EQ
(2) Geoff Daking 52770 EQ
(3) Great River NV EQ
(2) Vintech Neve X73i EQ
(4) Vintech 473
(2) Millennia Media STT-1 EQ (Tube or Solid State)

re

i'm really considering that one of the api 550 or 560, i am actually considering getting a lunch box and making a kick drum channel, getting a 512c then either the 550 or 560 (leaning more toward 550 cause its parametric) and then one of the 525 compressors, and have a nice little kick ass kick drum channel, i do mostly heavy/kick drum based music.

what do you guys think of that chain for a nice kick channel,

thanks

Check out my post under "Random Preamp Questions" topic. I think that an API Lunchbox is a great way to get awesome drum sounds. My friend in "Hotlanta" uses a pair of 512's, a pair of 550's, and a pair of API-clone compressors (he made them himself and used the infamous Allison Gain Brain as his model).Now he can do snare/kick micing like nobody else.
The 550 is an under-rated EQ. Everybody yells "Neve!", but the API is just as valid and musical (IMHO). I have a pir of 560 graphics that I have strapped across the stereo mix bus of my Neve Melbourne for years...no complaints here!