Best (budget) compressor for acoustic guitars

(..not sure where to post this..)
Hi there I know that this question and variations of it have been asked countless times, but I am am incredibly indecisive about which (budget) compressor to choose.
My choices have basically been narrowed down to these 3/4 options:

dbx 166XL
dbx 266XL
Behringer MDX2100
Behringer MDX2200

Can anyone please offer some insight as to which of these four would best suit compression (during tracking) of an acoustic six string guitar and also an electric bass guitar?

(I have very little money to spend and will be buying one of these items second-hand.)

The unit would also be used for recording vocals, but not as much as used for recording guitar.

PLEASE NOTE: I know that these are not "great units" and my money would be better spent on a better compressor and every other response that I've read in the internet. But between these 4, which would be the best for my intended purpose?

Please back up your response with reasons and better yet experience.

Thank you.
-S