Personally, I use a Garmin eTrex 30 (after replacing an eTrex 20 because I wanted to add HRM and cadence sensors/displays). It's not specifically a cycling computer/GPS as it has many hiking/geocaching features also. It's all but waterproof, lightweight, uses AAA batteries and has manageable/upgradable maps. Offline track analysis tools and route planning tools are freely available. You can use Garmin maps or OSM maps, 3rd party topographic overlays and create-your-own maps & overlays (again with freely available tools online).
I haven't found a feature I wanted that this doesn't have. I have used it as a car GPS but the screen is really too small for that when compared to 4" and larger car-GPS's.