I'm just using the default drivers for my HP deskjet 845c. It works fine.
I agree partially with you on that. However there are many features that cannot be accessed with out the full Hp software suite installed. Such as Scanning a doc into a file in a particular format, a letter into a PDF format for instance. Or scanning multiple pages in via the auto feeder. you can only do it one page at a time using the MS/Win Office Tools. One sheet at a time with doing a complete option setup between each page. In addition, you cannot use the fax features, the machine wont connect to the computer/vice a versa. The only solution is to disconnect from the computer and use it as a stand alone fax.
These are all features I wanted, needed and paid for when I bought the printer. The kids have a very similar Lexmark All In One, though several of the outer plastic pieces got broken during their last transfer, I checked the Lexmark site back at the end of Sept-first of Nov and they had Win7 drvr's avail. Likewise Cannon and several others. And I'm not talking just 1-3 yr old machines either. Some of the cannon listings were machines that sailed with Capt Ahab.
I really think it tacky of HP to think it's perfectly all right to make you do with out the features/services you paid for until they get ready to do something.