HDN 655E Haier dehumidifier does not look too good in internet reviews. 1 year warranty. Kenmore, I believe, also has a 1 year warranty, and some models did not have complimentary reviews.
Allergy Buyers Club lists what they call 'the best' at
Dehumidifiers for the Home, Basement and Crawl Spaces - Free Shipping & Expert Advice! with consumer reviews.
Howstuffworks also offers reviews at
Consumer Guide: Dehumidifiers Product Reviews Proper maintenance can extend the life of appliances. Vaccum dehumidifier coils and and evaporator fan on a regular basis. Unplug unit, wipe coils with rag to expedite drying, and when dry vacuum.
As long as humidity level is maintained at 35-55% year round, then you are good to go. Raising humidity level a bit might mean less work on the dehumidifier and extend its life expectancy. Going with a little more expensive unit with a longer warranty might help with life expectancy.