A friend of mine bought a Sportcruiser kit when they first apeared for about £35k (from memory) they are seling for over £60K now and I was told the new "Pipersport" is well over £100K
As for fuel burn Steve K is correct, we have travelled all round Europe in Rvs with Rotax microlights following and fuel burn is sililar as they are in the air for twice as long for the same leg.
having said that i have a pitts with an IO 360 that burns less on a trip than one of my other aircraft that has a Rotax 912s!!! so the can burn 27 litres an hour when instructed to!!!