Originally Posted by sdetweil
far as I know once you apply the tune, you no longer need the tuner attached, unless u want to use it as a monitor.
This is true to an extent. It depends on if you have other means of monitoring your vitals. If you do not, then I would argue that you do in fact need it plugged in.
Now, if you have other means of monitoring your truck's vitals or you have no desire to use it as a monitoring device, then why spend the extra money for that functionality in the first place?