While not using d20 Modern currently as my players and I have found we prefer WOIN: NOW for the modern day covert action game I'm running, I always loved the "Moreaux" concept in their Friends & Foes chapter, so much so that I worked it into the current campaign.
I did try to run a d20 Modern version of the old Top Secret module 002 (Lady In Distress) module that I converted, but I was a very noob GM back then and it didn't go so well. I think the conversion was fine, but my running of it was not. We also tried Spycraft 1.0 and 2.0, but while I liked it, my crunch-averse players did not.
On the whole, my players and I like the dice pool mechanic and the dice probability curves that come from a dice pool over a single d20 roll. I've seen the 2d20 alternative rule stuff, but we prefer throwing a bunch of d6s. I only wish WOIN:NOW had better support on Roll20....