go with the 1.8 for sure.
for the money, the 35mm 1.8 can't be beat. I have the 50 1.4 and used to have the 1.8...I rarely shoot the 1.4 wide open cuz it get a tad soft on the edges. but at 1.8 and up it's SHARP! the 1.8 was sharp from f2/f2.2 up. a negligable difference at that.
save your dough go 1.8.