I had an 1800w Purepower upright for a brief while, it was pure something (think of the victorian definition of "pure" and you'll get my drift), but it wasn't power, that's for sure...
Noisy, whiny, dimmed the lights, didn't clean well, I should have left it by the bins and just took the cable off it (that later got fitted on my Junior U1104), it was just not good in any way, not to mention the belt had run off the pulley and melted one of the things that locked the thing in the upright position, so couldn't even stand up for itself...
The only redeeming feature was that it was bagged, rather than being one of the bagless versions of the same model...