I've been burning onto my Verbatim Dual Layer DVD+R on my Pioneer 111d at the speed of 2.4x so far, and ive been told that it can be burnt at 8x instead. I dont want to have coasters constantly, can someone tell me if this is true or not?

I originally only burned at 2.4x because I didnt want coasters either. I have been burning at 4x on more recent games and have had no problems. 8x will work too, but slower speed is usually a better burn. I would try 4x and leave it at that.