I primarily use 2
I have an App called "Maprika" on my phone. And I have my Garmin Rino 650t
Maprika:
1. What are the pros of your unit?
It allows me to download all of the common area paper maps for use offline. It makes for a great sanity check for my map reading skills
When you have a data connection, it transmits your location to people on your "friends list" (maprika, not facebook) and receives their location. Very handy when people are scattered around for SAR operations.
2. What are the cons, or things you wish it did?
I wish i could download standard maps like MotionX for offline use.
3. How much was it and where did you purchase it?
Free app for your iPhone, iPad, or android device.
4. Can you load custom trials/locations into it?
I think so... I haven't tried.
650t
1. What are the pros of your unit?
The battery lasts a really long time
It's very bright during the day
You can swap out the micro SD card with different maps and data points as needed (you can also plug it directly to your laptop)
It transmits and receives locations from people you've programmed in to allow
It's a FRS/GMRS radio
It's fast to recharge, and has an available pack that allows you to run it off of AA batteries
2. What are the cons, or things you wish it did?
The screen is a little smaller than I would like
I wish I could figure out how to have it default to roads/trails rather than a strait line when I tell it to take me to a waypoint
3. How much was it and where did you purchase it?
I'm not sure how much I paid for it. I think I found it on Amazon. I believe it's been discontinued.
4. Can you load custom trials/locations into it?
Yes - I use the standard Garmin Basecamp software to preload waypoints and download my tracks
Any other info that I missed but should be included in a quality unit ?
I'm a fan of gear that has multiple uses. Both the GPS units I use also have communications. I like redundancy with everything, so anything that overlaps helps in that aspect.