I don't think you'd find much success in scanning for control channels. Your scanner will "latch on to" the first control channel it finds and use that until you get out of range. Problem could be that the control channel is for something that you are not interested in, such as a business, local utility, etc.
I've got a fair amount of experience with scanning the Minnesota and Wisconsion systems during trips from Louisville to Grand Forks. I programmed all the sites along my route and the talkgroups I was interested in monitoring. Fortunately I had a GPS device connected so the appropriate sites would be turned on/off.
The scanners I had in the past were the "older" siblings to what you have. This line of scanners isn't very friendly to large statewide systems such as Minnesota and to a lesser extent Wisconsin. That's due to memory constraints.
To overcome that, I had to break things down into regaions so as to respect memory limits. It took some research and lots of programming time, but was done successfully.
I've since got the 436 and 536 - they have more memory capacity and programming statewide systems isn't such a challenge.
