I have a pressure pro and it has worked fine.
I am now looking for a new system as the press pro really is behind the times in regards to what it looks at. For example, it does not tell you about a rapid release. (X number of #'s over X amount of time.)
I tried the Tire Traker (Note the spelling) which is also sold as the Hawkshead and I did not have too good of luck with it after two units. It just would not update and gave me false alarms.
So I have chosen to now to go with TST 507 SYSTEM. http://www.tsttruck.com/Product_List.html
(NOTE lower price here... http://www.plugitright.com/TST-Tire-Pre ... ystem.html
sold their a distributor.) It will do all the items I would like and it seems to have some of the best support and customer service around. (From my reading.) I will be ordering one of these in the next week.
So, as you can see, mileage will very for many. It all depends on your needs and if it will work in your coach. (Maybe I had too much interference or something with the Tire Traker even though I had the repeater.)
I will end with saying....It is a very good safety device that I feel people should be using no matter what the flavor.