After visiting The Hopkins website: http://www.nvisionsafety.com/TPMS and the Dorian website: http://www.doranmfg.com/rvtirepressuremonitors.htm, I called the Hopkins tech support folks and have come to the conclusion that the wheel sensors for these products are identical. The specs are the same and they are both made in China. There appears to be some difference in the monitor panels however with Hopkins claiming almost double the reception distance as the Dorian. The price seems to be more or less equal with both units. The Pressure Pro system that I purchased for Tom's bus is identical to the earlier Dorian unit but Pressure Pro is now an independent company that seems to be made up of independent dealers as I couldn't locate a Pressure Pro company per see on the internet. I really liked this system and would purchase it again unless I can talk Tom out of his.
Bottom line is all of these units seem to be very similar with the latest entry (Hopkins) claiming more range and a nicer monitor panel. FWIW
