Made by probably probably the most famous vacuum cleaner brand around, Hoover, the C2401 for many is the go to model for a commercial (& residential) back pack vacuum & there are several good reasons regarding why. The weight of the appliance really should not be too much as this can cause a difficulty in moving it from one destination to another.
Wet or damp suction can cause a solid build up, which subsequently can slow down (or in extreme cases block) air flow. They not only are bringing us the main one which has got least noise levels but then a one which can be also good at cleaning.
Smaller in size, lightweight and usually portable. However, like I said above -- it'll do a pretty decent job plus that's respect the DC35 is perfect for those who don't need the floor quite as perfect.
When I went to my mother's house one other day, I noticed she had two almost new upright floor cleaners within the garage. Always ensure any filter is undamaged and fitted correctly to avoid any dust leakage.