So, do you think that it could cause engine problem with one bottle?
I'm no expert but I would say no otherwise I would not have chanced it in my own car. I think I only read one thread with bad results and I think it was on a built engine, you know how that is sometimes , they have to find blame somewhere.
Why do you feel you want to add it? I would say if your not having any temp issues and your just trying to bring down temp more don't bother. Their own directions say adding to system maybe 5* degree difference and you may not ever see that by the gauge.
If you were going to track the car and really wanted to test it I would say what the hell. If you want to see the best results according them you must drain all engine coolant from block as well, then only water wetter and distilled water. Then if you tracked it and got temps of 200 or less it would be legit if not, then just another gimmick. Remember I left some coolant in my system. If you don't get the results go back to factory specs. You want to go back to factory specs for sure if your up north or ever driving in very cold conditions. Here in FL. don't have to worry about freezing to often.