use the water cooling, ball bearing turbos carry so little oil there is little cooling.
wthe reason you need water cooling is to keep the ball bearing cage intact as they are made from a plastic according to owen developments, so the water cooling is essential.
my gt3071r made a bit of a noise when running, but apparently it's normal due to the bearings doing their job or what not. was only noticeable on idle or switch off though, not so much on boost.