For the age of satellite parity is soon upon us. I can't help but believe better products and way more flexible pricing is around the corner. The much-maligned Globalstar just posted its first profits in 5 years. They have a new constellation of 24 new satellites, 18 of which have been deployed and the rest come this year.
Iridium has dominated since Globalstar's constellation failed. That is about to change and I know that they are working on a new fleet of devices as well. I am not saying this because I favor Globalstar at all, just saying that they are a very big player and they are coming back online soon and it will affect the market soon.
I have rented the following devices in the last year:
Globalstar GSP-1700. Not extensive wilderness use but was able to maintain a 7 minute call from the Green River underneath Flaming Gorge before losing it. Fix time was a surprising two minutes. Weighs 7 oz (the lightest satphone available in America I believe).
Iridium 9555. I was able to get a fix in three minutes at the confluence of Bullet and Kane Gulch in Grand Gulch, 1400 feet deep in the canyon. A five minute call with no interruption. Further down the canyon towards Collins Gulch, it took 5 minutes to get a fix. Clear as a bell with about a 4 minute call window then a disconnect. Pretty sure that was a function of the geography. I had very low expectations of reception down in a canyon that deep. Iridium has 66 satellites in low orbit at about 465 miles. Weighs 9.5 oz.
Inmarsat Isatphone Pro: A little funky as you have to gameplan the location of one of their satellites, which you can do with an on-screen satellite location guide that helps you point your antenna. Once I got a fix, in the same canyon as above, I had a great 10 minute, clear conversation without interruption. I think it was because one of the satellites that they have was almost directly above me. They have only three satellites and they are geostationary, as in they "stand still", but they are at over 22,000 miles up! This should also theoretically help signal penetration in deep topography. Useless at the poles (sorry Alaska!).Interesting tech and one to watch. About 10 oz.
I have also tried two of the newer generation 2-way text beacon/tracking devices: the Delorme Inreach and Briartek/Cerberus Cerberlink. In my opinion, these devices main attraction is the SOS functionality as I don't use the real-time tracking functionality at all. They both use bluetooth to connect to your smart phone and you use an app to construct messages and stuff. Of the two, I like the Briartek unit as it seemed to be less buggy once set up, the bluetooth connection was rock-solid and the unit itself is really bomb-proof. Customer service was EXCELLENT with them as well, which I cannot say about Delorme. As in: within three minutes I was talking directly to the president, who also heads up product development, about some of my concerns and questions. Awesome.
I brought the Cerberlink on a 125-mile 12 day walk through the Wind Rivers in August of last year. One of the main attractions is that they have an in-house rental program of $65 for two weeks including 20 160-character messages. Additional messages are 75 cents but be careful. People can send you messages via email and if you don't inform your chosen contacts to abridge their signatures, you can dispose of your included messages fast (I am in the real estate business and everybody has lengthy non-disclosure tags in their signatures). I ran a test transmission and chewed up 7 of my included messages when one of my contacts responded with a massive email signature. This was when I called customer support and was patched directly to the president (see above). They also let you include RSS feeds in the field (weather, politics, sports, ack!) which you have to be careful with too. One severe weather alert I received was almost 1800 characters. It would be nice if they allowed you to limit the amount of characters receivable via RSS on your profile page. You can create any custom RSS feed you want.
My main complaint with these new-generation text devices is that they weigh as much as a sat phone (both around 8 oz.) and it takes forever to compose, send/receive and verify transmission. You can send canned messages if you like, and they do have some stand-alone functionality, but in the time it takes to pull it out, pair it and send and verify a 160-character message, you could have had 2000-character equivalent conversation in real-time on a phone for roughly the same cost.
The Iridium Extreme is the first device (to my knowledge) that combines the functionality of the Delorme/Spot/Ceberlink devices with a ruggedized phone, but it is really expensive, so I'll stick to renting until form factor, functionality and pricing parity come into play in the next few years.
If you are looking for a good rental company that carries most of this stuff, Skycall Satellite here in Salt Lake is excellent. Russ, the owner, comped me a week-long use of the Inmarsat unit because he had no in-field feedback on it yet. Very flexible and knowledgeable and fairly priced.