i work on a lot of dept store bikes at my co-op and even the brand new dept store bikes are in need of a good tune up. they are adequate transportation, but it is the equivalent of driving a 10 year old geo. shifters are stiff, cables stick, brake levers are sub-par, but if you pedal you will get somewhere. the newish ones that we get we sell for $40 tops, most go for around $25.
last week i had to talk a girl into a gary fisher over a pacific. once she rode both about 10 feet she noticed the difference. its not hard to tell the difference in quality if you have ever ridden a properly tuned bike