While I used to have one identical to the wooden one on the right, I've never seen an aluminum Vega in person before. It turns out there are a few differences aside from the body material: the aluminum one has a 25" scale (vs 23" on the other one), and the pickup is subtly different. It appears to use the same coils and magnets, but the coils are separated by about 1/2" (with longer poles to make up the difference) and the entire pickup is further from the strings due to the thick cast top. The aluminum one therefore has lower output, but a more compressed sound. Its tone is also a bit mellower, but not extremely dark.
It took me a while to figure out what the white plugs were in the top of the cast body. After playing it for a while, I realized that they are 24th fret markers! Vega actually found a way to extend the fretboard beyond the frets. I think that Vega's main inspiration for the design was the National-Dobro aluminum steels. I say that partially because of the hole in the headstock, and partially because the board has a marker at the 20th fret instead of the 19th - just like many aluminum Nationals. I'll bet that the two-point body shape was taken from Vega's mandolins.
The wood-bodied steel sounds great as well. It sounds a bit brighter and has pretty hot output for a pre-War pickup. This would make a great rock and roll instrument. The sustain isn't as good as its older brother, but the brass top plate still lets it ring out for a while.
