I am looking at purchasing HKS camp gauge system for my IS since I have nav and limited space to put my gauges. Are there any cons to getting this system? As far as price, it will end up running in the 700s for everything, but it will be displayed on my nav screen, I wont have to cut holes or drill into my steering area to mount, or worry about installation places. What are the cons, if any? Does anyone have it on the IS? Thanks.