Daynov: Well, at first I had plenty fun engaging them, but it got pretty annoying fast as they didn't have a particularly hard time blowing my vehicles as I tried to drive past them (when I didn't feel like killing them
again).
There are many off-road routes to take that allow you to completely avoid most of guard-posts and encampments. Other than that, I've had pretty good luck blowing past them and/or losing them in chases - although my vehicle might take a certain amount of damage (up to a lot). Try more off-roading..
Daynov: I remember a particular moment that actually made me drop the game for several weeks that involved using the hang glider to get a diamond only reachable by flying. So, I totally fail to reach the diamond, drop right into the middle of an enemy camp, kill everyone, go again to try my luck with the glider, almost make it to the diamond location, get shot and killed by the same people I murdered literally minutes ago, because apparently the camp respawned.
The only diamond I can recall offhand that both 'required' a hang-glider AND you had to fly over enemies to get to it, was at the rail-yard. (I can think of other's that needed the hang-glider, but you didn't have to overfly enemies.)
For that one at the rail-yard, you can reach that one from the ground, if you park an assault jeep or that Fortune's Pack utility truck, or the 'big truck', on one side of the big rock, and climb atop the vehicle - you can then jump from the vehicle to the rock and retrieve the diamond - without hang-gliding over the rail-yard.
Was that the one? Or a different one?