i havent done the DP installation but I do have rhino ramps. depending on how big of a guy you are it may be slightly tight.. i am 6'3" ~200lbs and i can slide under the front no problem to get to, say, the oil drain plug.. maybe those who have done the DP install can speak more to the room for longer time installs.
if you do get the jack, i suggest you also pick up the aluminum jack pad... i would have gotten the jack if i had found this before i bought the ramps
http://burgertuning.com/BMW_jack_pad_adapter.html
it fits right into the build in bmw jack pads