Well, for sure it`s not the smoothest game out there,but I think it was programmed with more powerfull hardware in mind.
After all it runs ok on my 9 months old GF2ultra,but there`s allready a GF4,and the GF3`s price is gonna be under $100 pretty soon.
So wether we like it or not,we need to upgrade out computers quiet often,to keep up with this hobby.
I belive flightsims are the most demanding applications on the videocard when it comes to games.MOHAA does look great,but from 3000 meters You see way more than from the ground,and it`s the videocard`s job to draw all that terrain on the monitor.
If You decide to shelf IL2 You miss out a lot.