I have a 2021 P4X and I’ve had the Pedal Monster on now for a little over a thousand miles and thought I would pass along my thoughts. Bottom line, It does exactly what it claims and it does it very well. I will pass along a few details that are not abundantly clear before purchasing one. The reverse gear safety DOES NOT work with Nissan Titans though I never run my truck at such a high setting that this is not a concern; I started out at City+1 and am now at City+3 and feel it is the perfect setting with the low speed trim on +2. It DOES work with an OBD-2 splitter and a Scanguage, with both devices working as advertised. Lastly, my only frustration with the device is that every time I start the truck, I am required to reconnect the device with my phone in order for it to work. I wish this would just automatically occur. An aside, for the 500 miles I drove the truck I never experienced any of the bugs with the 9 speed that I have read about on this forum and since running the Pedal Monster, I find the trans to be quite impressive and rather intuitive. Lastly, for those of you with a scanguage and a truck with the 9 speed, they now have an Xguage for trans temp. I helped them out with this a while back by them sending me an obd scanner tool to find the parameter and it is now a set Xguage for trans temp at the pan.