Alternatively you can connect InReach to a cell phone by bluetooth, and use the phone's texting features.
As Dale points out, you can buy in cheap - if you don't use tracking. There's a very usable InReach plan that includes tracking for $25 a month.
SPOT uses a less reliable satellite network than InReach.
APRS works well too. 3-minute intervals for Lat/Lon, Alt, Heading and Speed.
Like a GPS logger, if not mounted properly any tracker will be unreliable.
Jim


On Thursday, March 10, 2016 at 8:50:30 AM UTC-8, wrote:
The down side is that the text format is a virtual keyboard where you have to tediously select each letter from packets of three much as in an old telephone keypad.