Are M-Audio headphones any good? Haven't seen, let alone tried, any.
Q-40 is really a nice headphone. Don't know about the other products of them though.
Check it in the head-fi, probably you will find nice reviews about Q-40.
the Q40 is easily one of the best basshead headphones in the price range, provided that you purchase Beyerdymanic DT250 pads to increase the comfort level. Their other headphones are old Ultimate Ears rebrands, which some people buy, as the original IEMs are no longer being sold.
I work in an airport, so I see a ton of headphones/IEMs/Earbuds. Older Apple Buds are probably the most common, followed by Beats(surprise), although I've seen far less of them lately. Lower level Sony headphones are also common, as well as Klipsch S4's.
On rare occasion I've seen an ATH-M50 or V-Moda M80, always nice to see those!