Awsome performance but have some ?'s

[knightm1120]

My trucks performance since installing my FU is out of this world. Not only will it fly when i want it to but so far it seems to be getting about 5 more mpg's. However I do have a couple of questions. Im getting the extra mpg's in the 120 race mode, the others only give modest gains, is this ok for my truck in the long run to leave it on this (except for towing ect. of course) im not dogging it out or anything, just driving normally in the 60 to 65 mph range.
I was also wondering if yall had a tune that would stop my truck from going into gear or something like that, If I stop at a store an just wanna run in for a second it would be nice to just leave my truck running but i dont want it to get stolen. I thought about the 25 valet mode but my truck would still be driveable to any thief. Please let me know if yall could do anything like this.
My pcm code is NVK5. Great product too by the way, been braggin on yall.