Another Isspro user here. I, too, am very satisfied. A couple things:
1) You need to look at the exhaust temp AFTER the turbo to see if it's cool enough for shut down. You need ot look at it before the turbo to keep from melting pistons if BOMBed significantly, pre turbo is also MUCH faster. Yes, my truck has two exhaust temp sensors.
2) You need to let it cool to 300. After shutdown, the hotter parts of the system may cause the turbo temp to creep up a ways past 300. Oil will start to coke at 370 which is what will eventually kill the turbo.
3) How you drive before shutdown does affect the temp but if you are towing (or modified and not towing) you need to see how hot things really are.