As someone who's also pretty experienced with the BF Injection, I can vouch for everything in the OP. It decimates off-road races, I don't know why people pick anything else. And putting a sticky bomb on the front, I do that too lol.
I feel like the Terminator behind the wheel, because no one can escape me. It's ridiculously fast, and you learn how to hop over barricades with it pretty quickly.
I've done tests with the Injection versus the Infernus and Entity, where I drove on the highway from the bottom of the map to the top. It takes about four minutes, no matter which of the three vehicles you use (and as a side note, that means it's basically always faster to take the road than to off-road travel, due to the ability to maintain top speed the entire way).
4) You can put it through terrible abuse and crashes, and the wheels don't really bend or deform. You can keep driving like if you weren't in any crash, even after you put your BF Injection through hell and back. This is a problem with the Sandking, as the body of the car can deform into the wheels and then you get that rumbling effect on your controller cause your car's wheels are now ruined and you go slower. The BF Injection doesn't have that problem.
This is the one thing I don't 100% agree with. You need to add some armor to it to prevent deformation, otherwise the front is pretty vulnerable. I doubt most people are driving around personal vehicles without armor, but something to keep in mind. A lot of the time the deformation doesn't prevent it from driving just fine though, which makes it look hilarious when you're cruising top speed in a vehicle that's horrifically mangled and has a tire aiming the wrong way.
But like I said, once you get some armor, deformation is a thing of the past anyways. And yeah, this thing is unstoppable.