We have a nanodrop in our lab. It serves us extremely well, and i really appreciate it - i was initially "broken in" on an older spectrophotometer (Beckman DU-800) that basically required you to sacrifice half your sample to get a so-so measure of DNA concentration.
Because we have a nanodrop in our lab, people often ask me about 260/280 ratios. Well, more commonly, they ask me about 260/280 ratios when things go poorly.
First, i should state that the gold standard for whether or not a DNA extraction is "good" (i,e. assuming you are doing PCR) is whether or not you can get it to amplify... with or without trickeration.
Second, for those still interested in 260/280 ratios and the presence of contaminants, i offer this handy little publication (from nanodrop/thermofisher), which i'll just refer to as number nine.