this thread is definately back from the dead. heres a few more random thoughts on it
no doubt histos & charts are WAY more useful for tuning , but I use the guages a lot since I commute to work 2 states away 6 days a week morning & evening for work.
I especially use a very big KR guage and a really big speedo that turns to red at 78 mph - comes in real handy since I dont use cruise often to keep the old speedo from creeping if you arent paying attention
pretty much have everything set to turn red if something is going wrong so you can see it without actually looking at the laptop.
I have thought of using the guage feature in a gutted car with the laptop front & center where the factory guage cluster was in a budget drag beater - so aside from all your other issues you face with the 39 I like that idea