Back to vacuums...
I've never found my Kirby G6 particularly difficult to use. It took me all of maybe two minutes to understand its features. Having rescued it from a dumpster, I didn't have the luxury of a manual or DVD to explain any of it to me; it's just that straightforward and intuitive. The height adjustment is actually easier to work than any other upright I've ever used, save for my Kirby Heritage, which works exactly the same way. It's designed to be operated on the fly and does it brilliantly.
Yes, the thing is heavy, but I have a one-story house, so there are no stairs to lug it up and down. It's also a bit of overkill, considering there are only two carpeted rooms in the whole house. But as a deep cleaning machine, it's a beast and a half, yet the Tech Drive lets it move like a machine that weighs half as much. It's a well-engineered machine, arguably the Hummer of upright vacuum cleaners.
Although I did eventually acquire a set of attachments for it, I never use them. For those applications, I prefer my 1969 vintage Electrolux 1205 or my recently acquired mid-'80s vintage Royal hand vac. In the end, it's all about using the right tool for the job.
Of course different folks have different ideas about what the right tool is. My girlfriend's sister used to clean my house and she never wanted to use the Kirby. She preferred to bring her $45 plastivac from home. It got the place clean and it worked for her. So be it. I prefer the machines I have and wouldn't want one of those disposable ones. Using built-to-last metal vacuum cleaners arguably helps the environment. I lived in an apartment complex for 10 years and I saw how many plastivacs went to the landfill from there each month. Multiply that by a whole city, and it's really frightening, especially considering and all that plastic is a non-renewable resource.