this is just to back Jeff's answer because he really deserves credit and support for making such a good product.
I both own a Medicom counter and a MightyOhm kit. I can say that although, as you might expect, the Medicom counter is more sensitive, with a conversion factor of 0.057 I get absolutely comparable readings. If you just want to have a feel for normal vs high, by all means go for the MightyOhm kit.
If you are curious, this feed is produced by the MightyOhm kit.https://cosm.com/feeds/64861