I agree, Garmin does indeed have many, overlaping products...I guess they want to offer something for everybody?
Their operational support for their actual units in the field is actually quite good, IMHO.
I bought a Vista hand held unit when they were fairly new. Garmin issued a software update via the internet that greatly upgraded the Vista's value. The update added many more waypoints, routes, etc. That's what I call 'support'. It also gives Garmin the chance to fix any screw ups in there products in the field, software wise.