I use Googe Earth for bearing, distance and it will give an elevation profile which is great for line of site issues. While I like the jack of all trades antenna concept, your single band yagi will perform much better and its much smaller. I plan on using a better GMRS only omni antenna at home (currently using a copper j-pole). For radios, looking for a couple mobiles.
I've been using this for simple line of sight. https://www.scadacor...-line-of-sight/ I like it. I'm sure the gmrs yagi is the way to go, I was just trying to save some time and money finding a dual band. The tram showed pretty low SWR for gmrs frequencies but the performance on gmrs is so so, I think. I did try to hit a standard uhf repeater in the area and was able to hit one about 25 miles away with it. If it stays sealed up, I think it's a keeper for a standard dual band omni.