We use a Garmin GPS III Pilot at work. In the past I've used a Garmin 190 or 195. Can't remember which.
I like the GPS III except for a few b@stard design faults:
2. Top of the list is the mongrel oval cursor button. If you don't press in exactly the correct spot then the cursor moves at 90 deg to the desired direction. Because it's a single button it's not possible to guarantee isolating one microswitch press from another. There's no markings on the pad to show exactly where to press. The number of times I've felt like throwing it out of the window through sheer frustration at trying to make the cursor go in the correct direction.
The cursor is only able to be moved in a single one of four directions so why they used a single button is beyond my understanding. Far better if they'd used four separate buttons, analagous to keyboard cursor buttons.
I think it was another b@stardisation of a product by a marketing/style department who know SFA about useability.
2. Battery compartment access: Can't change the batteries unless you remove the unit from its cradle. Another fine design from 'B@stards Incorporated'.
NB: We get about 6 hrs out of it with rechargeable NiMH batteries then another hour or two after the low battery warning first appears.
The 190 (195? Not sure of the exact model) I used was not as good. No map. Not sure about battery life since we always plugged it into the cigarette lighter.