We ended up purchasing the TireMinder SMART (with iPhone app) for $320. It has worked flawlessly (local driving and now on our first real trip) although I did need a good amount of help (not very mechanical handy, but learning, a lot) to have signal extender properly installed. Once installed, the setup has been very easy and again working beautifully, highly recommended.
Thanks again to all for input and guidance.
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2014 Allegro RED