I looked at the Monterra description for all of 10 minutes today, zipped over to GPSCity and placed my (pre)order destined to ship Oct 21 (or so.) It looks pretty much like what I have wanted for the last 5 years.
I will probably continue using my beloved 62SC, because it works so well. But this Monterra thing has some real potential, so I ordered one so I could check it out.
If you think of the Monterra as a fancy phone with no phone chip, it's expensive and a dumb idea. If you think of it as an alternative to (for example) a Trimble Juno T41 (starts around $1500) or other rugged handheld programmable data collector, it's probably the cheapest in that class by far. I have had 3 Garmin handhelds and a couple Nuvis. I have also had other handhelds including PocketPC and Android and Linux devices and a Delorme PN40. I always want to have flexibility in loading in my own maps and programs, and that's wanting with a GPSmap or a Montana.
I live in the Willamette Valley. It rains here, a lot. I have killed 2 cheap cell phones. A friend just killed a 4 day old Galaxy S4. Maybe it does not rain where you live. I don't want to put my GPS away if it rains. I still need to know where to go, even if a hike turns wet.
I actually dropped my Garmin eMap and rode over it while bike touring. Nary a scratch. I have dropped my 62SC off my bike once or twice. No problem. I can't imagine that my Google smartphone could take that. I think it would go to pieces. I have found probably 6 cellphones on the roadside while riding to work. None of them were functional. I need rugged.
Cell phone coverage is very spotty here. My Google Nexus phone sucks as a GPS receiver when it's out of cell range. The battery is too small. If I leave the GPS on, it won't last through 1/2 of a hike. No, I don't want to carry extra batteries. I gave up on using it for geocaching and got the 62SC. I don't even have a SIMM in the Google phone right now, back to using a cheapie little phone that has 4-5 days battery life and fits in a pocket.
The sun comes out here occasionally and when it does, my smartphone screen is worthless. Have to find deep shade to see it. That means it's pretty much useless on the handlebars on my bike. On the bicycle it's either raining (so I have to hide it away) or too sunny (and useless). I currently use the 62SC as my bicycle computer, speedo, cadence, map, and geocaching buddy all in one.
I also happen to be an Android developer, so while I hope that the Monterra works as well as the 62SC, if it's not then I think it will still be fun to write code for it.
Cheers
Brian