I really studied the market for these criteria:

6 out of 7 ain't bad. I got it for $139.95 at Best Buy which is way under the next unit I could find with a map, but it does not have a computer interface. The maps are limited to major roads and bodies of water, but what unit has topo maps for climbers for this price? I use a GPS to avoid missing turns on my way to climb, and to record the off-road hike details.

I use the Location Tool in Microsoft Streets and Trips to note the positions of route changes and climbing locales, then create waypoints (called "points of interest" by Magellan) in advance. I have had great success this way, while working around direct computer access.

I like this unit and for less than $150 including tax or shipping, I am very satisfied. I would give 5 biners, except for the computer interface. By the way, it has read as many as 4 satellites while situated in my windowless bathroom!

This is the easiest descender that I have used. It takes practice to get absolutely smooth, but it will allow you do controlled descents at nearly any speed.

I bought the Shunt for backing up rappels.
I use the Petzl Stop for doing the rappels.
I am currently using the Prusik on 7mm cord for backing up rappels. I say currently because there is a learning curve with the Shunt and the Petzl literature is not too helpful.