I just got the 430EX recently and I have had the 50 1.8 for a few months. It sounds like you will be needing the flash. I found that the 430 really lights up the living room well. You can really see limitations of the built-in flash, but the 430 provides excellent, even light when bounced off the ceiling.
I bought the 50 1.8 instead of the 1.4 because it was so inexpensive. I figured that I would use the 1.8 for a while and when I started to see the limitations of the 1.8 or if it breaks, I would upgrade to the 1.4.
I would say to get the flash, then decide on the 1.4 vs the 1.8 based on the advise provided on this forum. I think you will enjoy either lens - just make sure you know the advantages\disadvantages of the lenses. This forum provides excellect information.



