Hi there
I too have a 1.8 20v turbo, and of late I have noticed a little oil consumption may be half a litre in 2 months and 2500 miles, albeit hard miles !! Like you, no smoke or rattles. Its been remapped by the lads at Rtech and does get a bit of a work out. Saying that I have only just run it in ....110 K later !!
From asking similar questions myself it would seem that they do tend to use a bit, according to the handbook its normal
How much is it drinking ?