The scangauge and ultragauge do pretty much the same thing, they just have a couple different features. The scangauge lets you program in custom gauges (handy for hybrids and other fancy cars), while the ultragauge has a bigger and arguably nicer screen and is cheaper. I chose the ultragauge mainly for cheapness. Initial setup is as easy as plugging it in and finding a place to put it. I put velcro on the back of the little clip it came with and have it just to the left of the steering wheel. (Picture was taken to show the CR-V cluster I installed, just happens to show the ultragauge)
As luck would have it, the day after I put on a cardboard grille block, it rains. About 15 minutes of moderate rain at freeway speeds and 15 in city conditions. It is still together and didn't feel very wet. I'll see how it is tomorrow after it dries out. With the grille blocked, intake temps were 110-120F at freeway speeds and 60F outside temp, so it at least makes a difference there. Coolant temp was also lower at freeway speeds than usual, it usually spends a good amount of time at 203F, but today it stayed at about 197 and only hit 203 a couple times.
I have a feeling my car isn't running as efficient as it did in Utah (now I'm on the coast of California, in Monterey). I am applying more techniques now that I have a was to see what does best in real time, but at best I'm getting about the same results? Could the difference in air pressure be to blame? Or would a mechanical issue that just decided to pop up now be more likely?