John, I'm also on a tight budget, and went w/ a used OEM E55 H/E from a MB World forum member. When I posted looking for one, had great response from a few of the members there. Paid $90. shipped, for one w/ 23k miles on it. Besides its obvious dimension difference in the pic., it's also thicker. As great as the supercoolers are, I didn't like the idea of covering up my engine radiator. Running straight distilled water and (1) DEI wetter in the IC circuit right now. Don't know if this helps at all; just throwing it out there.