The Mighty Mite doesn't have a powered floor brush for carpet and is poorly filtered. The upright won't do well on hard floors. A good canister with a powered floor brush is what the original poster probably needs. Two beans will buy you a Panasonic MC-CG902, a much better vacuum than either the Electrolux or the Mighty Mite. $150 will get you a Kenmore Lime Green canister, not as good as the Panasonic but still better than the Electrolux and the Mighty Mite. Use a Kenmore cloth HEPA Q bag in either the Kenmore or the Panasonic and change the pre motor and exhaust filters every six bags and it will stay clean inside and last a decade or more if you don't abuse it. Treat it like a mega buck Miele and it will last every bit as long.
I bought an Electrolux bagless vacuum for $250 and the best I had used till date. Its so simple to use and does really well on hard floors though an upright one. Considering the use on hard floors and upright used this is a good choice to buy.