They are right for some people... not for others.
When it comes to vivid colour with a quality 'feel' then they are about as good as it gets. The wax on the paper makes prints stand out even on cheap paper.
However if you ever need to hot laminate your prints then they are not for you. It melts the wax.
Running costs are better than most HP's using OEM consumables, but not as good as the Kyocera C5300 for example.
Depending on what you print (coverage and quantity) it may also be worth looking at Xerox Pagepack contracts as they offer great value if you are printing high coverage colour.
'Green' credentials are good, since the consumables are just wax blocks with minimal packaging.
One piece of advice... If you do get them, do your best to never, ever turn the printer off... It has a decent powersave mode, and switching on/off triggers a cleaning cycle which wastes a fair bit of wax.