In another month or two I'd be able to give you a definitive answer as I have a 103R in an aluminum body coming back from Soundsmith. I've used 103R's in wood bodies (ebony and clavellin) for about 4 years; my current cartridge is a 103R with a $250 Soundsmith retip in a Uwe ebony body.
Bear in mind that even the different woods have different sonic signatures. For example, I much prefer the ebony to the clavellin which seemed to be quite a bit harder sounding and a bit tipped up with a less powerful bass than the ebony. Tighter perhaps, but less powerful. But system synergy and subjective listener preferences are at work with all this stuff and what I prefer may be the opposite of what you are looking for.
I never used the aluminum body before transplanting a 103R into it shipping it off to Peter Ledermann but I would expect the aluminum body, when it comes back to do some things better (again, subjectively) than the ebony while perhaps exhibiting some less likeable characteristics. My guess is that the aluminum will be very explosive and dynamic, more so than the ebony, but perhaps be a little harder and more analytical sounding as well.
My current cartridge leads (on the ebony bodied, SS retipped 103R) are silver and, generally speaking, I am not a fan of silver-don't have it anywhere else in the system. My plans, when the aluminum body comes back, is to switch over to copper cartridge leads to offset some of the hardness that I think the aluminum will bring to the table relative to the ebony.
Either one, aluminum or wood, will be a huge improvement over the stock plastic body, and combined with a retip with a good stylus like Soundsmith's the cartridge becomes a giant killer. For either cartridge (aluminum or wood body) to fully realize its potential, though, it will need a high mass arm. With the aluminum body, which is heavier, you need to get into the 20-22 gram effective mass area. The wood bodies are a bit lighter but still quite a bit heavier than the stock plastic shell; with those you need to get into the 24-25 gram effective mass area for the cartridge to really shine.
