On my last build I used brass furniture. Turned out nice enough, but brass dulls and needs to be shined up once in a while. The gun I'm building now has all steel furniture and I've not found it any harder to work with, other than it is a little more involved to sand than brass, but not prohibitively so. Not sure what kind of tools you have, but if you have access to an air compressor and a die grinder with abrasive and scotchbrite discs, you can get those sand or wax cast parts looking shiny in a short amount of time. I used my die grinder and the aforementioned pads and discs to good effect. A Dremel is meant for minute work and can't hold a candle to a die grinder for removing/polishing metal.