Simple, reliable and strong bike. Added: Kick-starter kit, good tyres, bark-busters, B&M bash-plate, force radiator guards, higher handle bars.
Needs a 6th gear. The factory restrictions need to be removed in order to use the thing.
Price. electric start. reliable. easy to work on. easy to install kick starter and modify the bike.
Comes with side stand and clutch lever kill switches however these are easily removed. The speedo is bulky.

excellent bike that goes anywhere the more fancier bikes can go with less fuss and surprises and you don't need to set a scedule for oil changes every 500klms like the other enduro weapons
easy bike to live with,with low maintenance required to keep it going
ergonomics for taller riders needs adjusting such as handlebar risers,pivot pegz and 1" longer gear lever

I bought my 2010 model in march last year, i bought radiator guards, bashplate, acerbis headlight and taillight, renthal bars. The bike is fantastic, i looked into wr450's and since i do a lot of trail/enduro riding the maintanance would have been to frequent. The airfilter is easy to get to and the yellow looks traditional suzuki and stands out. I will only get drz400's from now on. A great bike for everything!
Price, at least 3 grand cheaper than the 450's, makes good power, will get you anywhere, a great bike to get around town- yet can still do the dirty weekend work.
ugly headlight, ugly rear taillight plastics, the suspension is OK but with my 90kg it can bottom out over jumps.

They are a good reliable cheap to own bike. Power & torque is good enough for the average rider. Only a few add on mods required to make it ride better. I would not buy another due to its weight, would probably pay more for a KTM, however due to reliability it would make an excellent second bike.
Cheap and reliable bike for trials and getting around and having fun.
You would need to spend about $1000 to get better handle bars and high rise kit, bark busters & smaller rear sprocket (45 tooth) plus remove all the extra weight. The bike is a bit heavy for tight tracks and hilly / rocky work but does manage well. Standard suspension not really suited for heavy off road work, however its good enough.

Such a great bike to ride, if we ever have a nuclear war two things will be left Cockroaches and DRZ400. It is such a fun bike to ride and with some simple mods $1000 (Suspension, Bark Busters, Bigger Back Sproket, Bar Raisers) you have a serious weekend weapon for $8000. Just to clarify it won't be as good as some of the more serious Enduro Weapons KTM, CRF but if you are starting out or not into serious enduro racing this is the bike for you.
Cheap (brand new I saw a price of $7000 in a shop in Melbourne) Easy to Maintain and Service yourself. Loads of Power for a 400 in Mid to Low Range very easy to Start.
Handle Bars too low, front springs way too soft for serious off road riding, feels a little heavy for single track work.