I returned the water via the stock fitting into the block (just had a blanking bolt in there, but was actually drilled/tapped right through already). For the oil return I tee'd into the head oil drain.
As for reliability, turbo went on in mid-2009, still going strong Haven't actually ever had it on the dyno, so no idea what power figures it's putting out, but sees 10PSI all day long without an issue (running an eManage Gold piggyback). That said, it doesn't actually get driven much these days, so it's only done a little under 50,000kms in that time, and very little track work.