I have four different brands of trailcams and none of them have a viewing screen. In my opinion, I don't think it would be worth it for several reasons. First of all, most of the viewing screens are so small you can't really tell a whole lot about anything. Secondly, I don't know about you but I wouldn't want to stand out there getting eat up by mosquitos while I'm scrolling through the pics. I also don't like to stay in the area for very long to keep my human presence to a minnimum. Some alternatives for you could be to buy one of those digital picture frames they sell at wally-world, or just about anywhere else, for 79.00 and keep that in your truck and then you can view them when you come out. If I can't wait till I get home to view my pics, which is every time I check them, I just bring along my laptop. It is also a good idea to have two cards for each camera. That way you are not bringing your camera in and out all the time. Whatever you decide to do, have a blast!! Hope this helps.
Blessings.....Pastorjim