[travelin texans]

The experience I've had with the inline gauges on the propane is that it's accurate twice, full & empty, nothing in between & my changeover does the very same thing without spending more $$ on the gauge.
There's a newfangled propane measuring system out now that sits under the bottle with a remote gauge inside & if I recall Bluetooth to your smart phone, but for no more propane than we use in a year I could fill my 30 lb bottles several times for the price of that system.